Digital Signals FAQ Version: 5.0               +--------------------------+
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Last Update: Aug 23, 1997                      |         |     |          |
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Copyright (C) 1995,1996,1997 by Stan Scalsky   |  |||  ||||| |||||  |||   |
Copyright (C) 1995,1996,1997 by Mike Chace     | |||||||||||||||||||||||  |                      | ------------------------ |                             | D I G I T A L  R U L E S |

Portions Updated 21-Apr-2001 by Worldwide Utility News

Changes made for Version 5.0

- Added LESW, new 39-tone modem, HELLSCHREIBER, Mazielka, DGPS, CODAN
- Enhanced VFT section, fixed CLOVER-2000 tbl errors, updated MS5
- MIL188, COQ-82, Twinplex, RAC-ARQ, CROWD36, IRA-ARQ, PSK
- New Decoder info on Code 3 Gold, Wavecom W4100DSP and W41pc, Shareware
- New Section - ACF Summary
- New Appendix section

Changes made for Version 4.0

- New modes info, 36-50, 4+4, 1200-FSK, NATO, VFT, PSK and mystery modes
- New Reordered VHF info, added new FLEX, POCSAG, ERMES, NEC-D3 info
- New info added for Amateur modes
- Expanded Alphabet Tables
- SELCAL info added w/New Table
- References section updated

This Signals FAQ is a collaborative effort, maintained by Stan Scalsky and
Mike Chace.  Any questions, comments or corrections will gladly be accepted.
The authors imply no guarantee on this information and do not claim to be
experts or professionals in the field of signal monitoring. All information
has been gathered from public domain sources, manufacturers documents, decoder
documentation, real time analysis and any radio related publication that cares
to write about digital signals. We have tried to research for correctness each
mode listed but it must be said that there are a lot of inaccuracies and dis-
information present in the mainstream press. It is therefore a safe assumption
to assume that those inaccuracies could also appear here. 

Many thanks to those of you who post logs, information and answer stupid 
questions in the various forums that cover digital signals - you know who you 

  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
  NOTICE:  All contributors of information, tidbits, comments and corrections 
  will be considered confidential when constructing this document.
  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
  A word of Caution:  the rules  about listening  to signals not intended for
  you  applies  here.  The  contents  of  many  signals  might  be considered
  sensitive by  the party  sending and  the reception  of such signals may be
  illegal in your country. The authors neither condone or encourage such acts
  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

I would like to solicit material, to be included later, on any other analysis
techniques and/or DF techniques the utilities community is currently using.


                             TABLE OF CONTENTS

Section 0 - Introduction
Section 1 - Modes on Shortwave
  1-A.  Single tone systems
  1-B.  Synchronous data block systems
  1-C.  Packet-like systems/Asynchronous data block systems
  1-D.  Multi-tone systems/MFSK systems
  1-E.  FAX-like systems
  1-F.  SSTV modes
  1-G.  Synchronous bit stream systems
  1-H.  Asynchronous bit stream systems
  1-I.  Multi-channel systems
  1-J.  Phase Shift Keying systems
  1-K.  Mystery systems
Section 2 - Modes on VHF
  2-A.  VHF Data Signals
  2-B.  Special Amateur Digital/Video Modes
  2-C.  VHF SELCAL and Analog Paging Systems
  2-D.  VHF Digital Paging Signals
  2-E.  VHF Two-Way Paging Signals
Section 3 - Baud Rate Summary Table
Section 4 - ACF Summary Table
Section 5 - System Parameters Summary Tables
  Table 5-A - Synchronous Data Block Systems
  Table 5-B - Asynchronous Data Block Systems
  Table 5-C - Asynchronous Bit Stream Systems
  Table 5-D - Synchronous Bit Stream Systems
  Table 5-E - Multi-tone/MFSK/PSK Systems
  Table 5-F - Twinplex Parameters
  Table 5-G - Alphabets
  Table 5-H - Crowd-36 Tones and Alphabet
  Table 5-I - 5/6 Tone Paging Parameter Tables
Section 6 - What decoders are available
  6-A. Professional Units
  6-B. Hobbyist Units
  6-C. Public Domain Units
  6-D. VHF Specific Units
Section 7 - References
  7-A.  WWW Resources
  7-B.  Magazines and Books
  7-C.  Frequency Databases
  7-D.  Tape & CD References
Section 8 - Appendix
  8-A.  Abbreviations
  8-B.  Emission Classification

Section 0 - Introduction

This Signals FAQ is designed to give utility listeners a sampling of the
kinds of signals and sounds available on shortwave/vhf radio today along 
with information on the available equipment needed to understand, analyze
or identify these signals. Our primary focus is to present the parameters
that define the most commonly heard systems as an aid for utility monitors
and not an exhaustive discussion of HF digital signalling theory. It is 
also our intention to give monitors a best guess clue as to who the user 
of an unconfirmed signal may be.

With conditions being dismal over the last few years coverage of Utility  
Listening, especially Digital Utilities, has been dropped from most of
the main stream shortwave magazines. But in and of itself, Digital Utility
listening is inherently more difficult than regular shortwave listening.
The possibility of decoding the signal received adds another level of
complexity.  This FAQ is an attempt to let those beginners who are thinking 
of or wondering what digital signals can be received and decoded and maybe 
provide the more advanced listener with a little more information to identify
those unknowns. 

Here in lies the basic problem with digital utility listening - lack of 
information. Many systems are used by Military or Diplomatic Services 
and information on the specifics of a particular mode are impossible to 
find, even from the manufacturer. Many are considered proprietary, but that 
doesn't mean that a signal can not be identified! With the proper tools a 
given signal can be identified via the way it sounds (aurally) or how it 
looks (visually). Most decoders that include some kind of signal analysis 
can ID a signal by bit-pattern or baud rate. Many signals have a unique baud,
i.e. 300 baud packet, 240 baud HC-ARQ or 164.5/218.3 ROU-FEC. Once a signal is
identified there are many decoders that can print the traffic for you but keep
in mind various kinds of encryption are commonly found in use with these 
signals. Encryption types include figure group or letter group messages and 
even random bit-masking or bitstream encryption, which looks like a continuous
stream of random characters. You may often read the term "on-line" and "off-
line" used in conjunction with various encryption schemes. Generally, off-line
encryption is taken to mean groups of letters or numbers (most usually groups
of five), whereas on-line schemes just appear as a continuous stream of random

Keep in mind that you must be able to find a signal before you can apply the 
power of the decoder on the signal for identification and possible decoding.
Most signals found on the airwaves today are obvious with easily distinguish-
able sounds, from chirping to two tone FSK to musical multitone MFSK, but 
as communication technology develops this will most likely change. It is
safe to say that the more efficient a modulation/coding method is, the more
noise like it must become. I have heard it said in some digital groups that
"Any sufficiently advanced communication is indistinguishable from noise".

And now a word about decoders... 

There are many kinds of data decoders available ranging from public domain
packages to professional dedicated units. Prices vary from free up to very
expensive and price is dependent on how much you want to be able to decode 
and what tools are available for signal analysis and identification. Public
domain packages, while good, can not compete with the capability provided
by the more expensive dedicated data decoder unit. It is safe to say that
price goes up with increased capability in this market - be prepared to
spend some big money if you want to cover a lot of modes. A good rule of
thumb is that a top-spec decoder will cost as much as a top-spec radio, i.e.
upwards of 2,000 dollars. You'll also need to decide upon whether to buy a 
stand-alone decoder or one that requires a computer to run. The latter option 
will of course increase the cost if you don't already possess a machine, but 
does add flexibility to a decoder.  See the Decoders reference in Section 5
for unit specifics on capability and pricing.

What should you look for in a decoder? Some useful features include:

-        Signal Identification
-        Accurate baud rate measurement
-        Correlation Bit Analysis
-        Variety in modes decoded/identified
-        Ability to save captured text (disk and printer)
-        Tools for analysis

You can't beat a good Signal Identification Mode, both the Wavecom units and 
Hoka units include this option. Also, more recently some Trialware software
(RadioRAFT) is including Signal Identification. A good Signal Identification 
mode simplifies the task of figuring out what mode is currently tuned, but 
keep in mind that even the best Identification mode is not always 100% correct.
A common problem is that some keying systems share common idle characteristics
(for example: SWED-ARQ, SITOR-A and TWINPLEX or SITOR-B and POL-ARQ) and 
active traffic is needed to correctly identify the exact mode. Also the 
presence of local interference, various propagation effects, or a noisy signal
can make it difficult to correctly identify. Universal decoders do not include
an Identification mode.

Accurate measurement of baud rate is another vital capability. Many modes can 
be accurately identified on baud rate alone because many rates are unique to 
a keying system. It also provides the opportunity to "fingerprint" a signal,
system or the user.  For example, the Hoka decoders can measure baudrate
accurately to 3 decimal places in the presence of a quality signal but also
do well on marginal signals, eventually settling down on a reasonable
measurement. If your signal is full of noise you might not see 3 decimal places
but at least on Hoka decoders you will have displayed those decimal places that
make sense - a very nice feature. Universal decoders have trouble with accurate
baud rate measurement on the faster keying systems (for example: 192 ARQ-E) and
noisy signals can be particularly confusing resulting in some very odd numbers.
I don't have any direct experience with the Wavecom line of decoders so I will
not offer a comparison here.  See the Baud Rate Summary Table in Section 3 for
further information.

Autocorrelation Bit is a technique that samples the incoming digitized bit 
stream and presents the data as a graph of bit occurrences plotted against 
time. This will show when patterns occur within a signal, allowing you to
determine the number of bits in a character frame (this is commonly referred 
to as the ACF), giving you another piece of information when working out an 
unidentified system. This kind of analysis tool reveals cycle period and shows
when there are NO patterns in a signal indicating an encrypted or random
bit-masked signal, allowing you to move quickly onto more productive signals.
Hoka and Wavecom decoders include autocorrelation bit modules. See the ACF
Summary Table in Section 4 for further information.

Mode variety is a personal preference. I would like to have a module for
any mode I can receive in the spectrum! While not possible or realistic I
will take as many as I can get.  I find there is nothing more frustrating
than being able to receive a clean signal and then not being able to 
identify or decode it (ignoring the problem of encrypted signals for the
moment). As of this writing it seems that Hoka offers the largest variety
of modes, followed by Wavecom and finally Universal. See the manufacturers 
listing in Section 5 for the modes decoded by various units.

The ability to save decoded output to a file and/or the printer should be
considered a very important feature of any decoder. Having some form of
hard copy, on disk preferably, allows for archiving for later reference
or later analysis and independent printing and editing. Hoka decoders have 
the ability to save decoded text to disk or output to the printer. I believe 
Wavecom units have a similar ability. Universal decoders support direct
output to a printer and with some software can capture to disk.

If you are interested in going beyond the Identification and decoding of 
signals heard on the air you are going to need tools. Tools such as Spectrum
Analyzers, Character Analysis and Phase modules are some of the necessary
tools needed to analyze today's modern systems. This is, for obvious reasons,
not for everyone. As of this writing, Hoka and Wavecom, provide extensive
tool sets for analyzing signals. Universal decoders provide primitive tools
sets but in all fairness, Universal decoders are not really meant for analysis
but rather are best used for decoding known systems. Shareware/Trialware
software is starting to include more sophisticated tools. See the listing of
manufacturers in Section 5 for details.

I also like a responsive manufacturer who regularly updates their decoder in 
line with developments "on the air".  Variations on existing systems and 
completely new systems are still appearing today. See the table in section
1-K for some examples.

Section 1 - Modes on Shortwave

What modes are currently on shortwave? This section attempts to present a 
little information about each kind of signal that can be heard within the 
shortwave spectrum. Signals are grouped together by the way they sound. 
This is an attempt to narrow the field of possible signals when trying to 
identify an unknown. The typical baud rate(s) of the signal is mentioned, 
if known, and any other synonyms or possible names are given. But ... don't
make the assumption that these are ALL the modes you will ever hear. There 
are many signals that remain unidentified. See section 1-K for an extensive
list of unknowns.

For specific details concerning modulation, framing and alphabets used by
any of the following signals see Section 4.0 on System Parameters.

1-A. SINGLE TONE systems. 

  Single tone systems are becoming common these days with the classic Morse
  still in use and found in most utility bands. Newer single tone systems
  using Phase Shift modulation are starting to appear and are supposed to
  perform well in poor conditions.

        CW              Morse code still used by the Amateur community and
                        Marine operations. Speed varies depending on whether 
                        hand generated or machine generated but rates varying
                        from 10-400 can be found. Most often found using either
                        the standard or Cyrillic Morse character set.

        LINK-11 LESW    There is a new Link-Eleven Single-tone Waveform (LESW)
                        specification. It features an 8 phase PSK (DCPSK,
                        Differentially Coherent PSK), scrambled, 1800Hz tone.
                        The system is supposed to be good against poor HF 
                        conditions and problems such as multipath and fading.
                        Throughput rates up to 4800bps occur with block inter-
                        leaving of 0, 1.2 or 9.6 sec delay. Each packet has
                        192 bits (80ms) + 64 bits sync (26.67ms), each frame
                        carries 72 bits of user info and the last frame always
                        contains a 72 bit stop sequence. See MIL-STD-188-110A
                        or NATO STANAG 4285. This waveform is implemented in the
                        General Atronic GA-122 HF modem or the Harris RF-5254B.
                        Swedish diplo stations use a derivative of this system
                        from Rockwell/Collins (Mediaware).

                        Single tone modems sound like 3kHz of noise.

        HF=Datalink     An ACARS-like system used between airplanes and ground
                        stations for passing tech info is now operational on HF.
                        The system is an adaption of the MIL-188-110A single
                        tone waveform modem and uses 8PSK modulation at a rate
                        of 3600chips/s. Ground stations broadcast system manage-
                        ment uplink packets ('squitters') every 32s on 3 or more
                        active frequencies. This assists in finding error free 
                        channels. Adaptive rates of 150, 300, 600, 1200 and 1800
                        bps are supported. See Monitoring Times 6/95 Plane Talk 
                        or the Digital Review column in WUN 10/95 (V1/10) and 
                        WUN 11/95 (V1/11) for more info. Also known as HFDL or
                        ACARS on HF. You may see this referenced as ARINC 753.


  Signals of this type generally sound like SITOR-A - a distinctive chirping 
  sound is their main characteristic. Short SWED-ARQ sounds and is exactly 
  like Sitor-A. Idling TWINPLEX is the same as Sitor-A. To identify these 
  signals by ear may be impossible depending on which mode they are currently
  in. A decoder that can determine signal type may need active traffic to 
  correctly identify the mode currently tuned.

        ARQ6-70         A simplex ARQ system with a 70 bit block length using
                        the ITA3 alphabet. A regular user is unknown but the 
                        French Diplo service has in the past. No loggings have
                        been found for quite some time and no loggings have 
                        been reported in the previous year via WUN.

        ARQ6-90/98      6-character-block simplex ARQ used by French and
                        Italian Diplo services, typically 200 bd. ARQ-6/90
                        and ARQ-6/98 differ in their inter datablock timing.

        G-TOR           Golay Transmission over Radio. A system developed by 
                        engineers at Kantronics, Inc. Users of this system 
                        include Military (Irish Air Corp, Irish Navy, Mexican
                        Army), governmental agencies (ICRC) and the Albanian 
                        Christian Network (ACN). See WUN/Utility Round-Up 2/97
                        (V3.2) for more information on the ACN. 

                        G-tor's "claimed" main advantage is speed - up to 4x 
                        faster than pactor. It also incorporates a data inter-
                        leaving system that assists in minimizing the effects 
                        of atmospheric noise and has the ability to fix garbled
                        data. G-tor tries to perform all transmissions at 300bd
                        but drops to 200bd if difficulties are encountered and
                        finally to 100 bd. All acknowledgments (ACK's and 
                        NAK's) are sent at 100 bd.

        SWED-ARQ        Swedish Adaptive simplex ARQ used by Swedish Diplo
                        services, typically 100 bd. Comes in the 3 packet
                        lengths: 3, 9 and 22. Universal literature refers to
                        this as short, medium and long. The system is able to
                        change packet length in mid transmission, depending on
                        conditions, giving SWED-ARQ its adaptive capability.
                        Also known as ARQ-SWE.

        TWINPLEX        4 frequency diplex system used by organizations such
                        as Interpol and United Nations and the government Diplo
                        services of countries such as Australia, Denmark,
                        Holland, Norway, Pakistan and Spain. Typically runs at
                        100 and rarely at 200 or 300 bd. This 2 channel system
                        supports several different shift parameters and word, 
                        bit, character or not-interleaved of the channel 
                        characters but is easy to identify because of its 4 peak
                        signal. Reference Table 4-F for all the parameters. This
                        system was developed by Thrane and Thrane of Denmark.
                        Also known as F7B4 or TWINPLEX-SITOR.

                        Also see Section 1-H, BAUDOT/F7BBN, for another form 
                        of TWINPLEX.

        SITOR-A         The most common ARQ signal used by Amateur, Marine and
                        some Gov. Diplo services, typically 100 bd. SITOR-A is
                        most commonly monitored with a 170Hz shift but stations
                        such as MOI Spain have been monitored using a 400Hz 
                        shift, Guardia Civil, Spain have also used a 400Hz wide
                        shift, the Spanish Air Force has been using a 300Hz 
                        wide shift and the Norwegian Navy has been found using
                        300Hz and 850Hz shift. Also known as ARQ or TOR.

                            Common User                    Shift (Hz)
                            ----------------------------   ----------
                            Amateur, Marine, Gov. Diplo    170
                            Spanish Air Force              300
                            MOI Spain                      400
                            Guardia Civil, Spain           400
                            Norwegian Navy                 300 850

        SI-ARQ          Siemens Simplex ARQ used by Austrian and Indonesian
                        Diplo services, typically 96, 144, 192 or 200 bd.
                        Also known as ARQ-S or ARQ-1000S.

        MERLIN/ALIS/    Rohde & Schwarz simplex ARQ, so far found in use by 
        RS-ARQ          German, Italian (MFA and GDF), Nairobi and Turkish 
                        Diplo services, typically 228.7bd but reports of 457.0
                        have been noted. Usually found with an ACF=59.

                        There appears to be no "real" name for the data system.
                        Now referred to in Klingenfuss documents as ALIS but
                        strictly speaking, ALIS is only the automatic link 
                        processor and frequency management system. It is not
                        responsible for generating the traffic. ALIS is there-
                        fore somewhat of a misnomer. The modems generating the
                        traffic are the GM857 and GM2000. Our suggestion is to
                        stick with RS-ARQ as the system name. 

                        Many of the diplo users actually control their networks
                        with MERLIN, the name for the R&S complete data-over-
                        radio and message handling system that can transparently
                        deal with many types of data (fax and voice included).
                        Consequently it has many modes. See Klingenfuss Radio-
                        teletype Code Manual 13th Ed. under "ALIS" for more
                        information. Formerly referenced as RS-ARQ in the 12th
                        Reference section 1-D for the multi-tone ALIS-2 system
                        and section 1-C for a packet-like MERLIN system.

        DUP-ARQ         A semi-duplex ARQ system used by the Thai and Hungarian
                        Diplomatic service with unconfirmed use by at least one
                        other Far Eastern Diplomatic service so this system is 
                        not unique to the Hungarians. Baud rate is typically 
                        125 bd using ITA-2. If a DUP-ARQ system detects inter-
                        ference it will change frequency in 400Hz steps. If a 
                        3kHz channel is full of interference the system will 
                        select another frequency. Also known as ARTRAC, or 

        DUP-ARQ-2       An ARQ system with the same block timing as DUP-ARQ
                        but runs at twice the baud rate - 250 bd and uses the
                        ITA2 or ITA5 character set. Recent DUP-ARQ systems now
                        auto-switch to DUP-ARQ-2 at 250bd so this system is
                        really an enhancement to the original DUP-ARQ system.
                        Automatic channel selection and channel hopping are 
                        still supported. Also known as ARTRAC II. First listed
                        in Klingenfuss 14th Ed. Utility Guide. This system has
                        been monitored sending foxes de stc.

                        Probable DUP-ARQ-2 signals have been noted on 13459,
                        13462, 14873 and 16061Hz. Look for the characteristic
                        channel hopping.
        IRA-ARQ         Duplex ARQ with IRA (ITA-5), used by Czech/Slovak
                        Diplo stations (MFA Praha, CZE), typically 171.42, 
                        200.2, or 300.3 bd. This system uses an 11 bit 
                        character and the signal has some very wide ACF
                        values, ACF=352 or 448 have been recorded.

                        A tip for monitors is to remain on frequency with the
                        decoder set to ASCII/ITA-5 at the same speed that the
                        ARQ is sending. Once the transfer is complete, operator
                        chat often takes place in standard ASCII or BAUDOT.

        PACTOR          A system designed with a combination of packet and
                        sitor techniques used by amateurs, MARS stations and
                        many quasi-governmental organizations. Mutually incom-
                        patible variations are becoming common with changes
                        made to the packet structure to support privacy re-
                        quirements of the various quasi-governmental users. 
                        Commonly referred to as UN-pactor, ICRC-pactor or 

                        The developers of Pactor, Special Communication Systems
                        (SCS), have licensed their hardware and software to
                        Schuemperlin Engineering AG which has actively pursued
                        commercial acceptance of this protocol and as many as
                        7 different variants have been noted so far. Code 30
                        defines the following variations:

                                        Common User           Label
                                        --------------------- --------
                            Pactor 1    Amateur               PACTOR
                                        Non-Governmental Orgs
                            Pactor 2    ICRC                  PACTOR-I
                            Pactor 3    UNHCR                 PACTOR-U
                            Pactor 4    IFRC
                            Pactor 5    UNO/MSF ?
                            Pactor 6    included in Code 30
                            Pactor 7    included in Code 30

                            Don't know if Pactor 5 is the same thing to Wavecom
                            and Hoka and who the users of Pactor 5,6 and 7 is

                            ICRC - Int'l Committee of the Red Cross
                            UNHCR- UN High Commissioner for Refugees
                            IFRC - Int'l Federation Red Cross and Red Crescent
                            UNO  -
                            MSF  - Medicins sans Frontiers

                        Pactor I is the original implementation and is also 
                        known as FSK Pactor. Pactor II is DSP based and is as
                        much as 8 times faster then Pactor I.

                        A Pactor Level II signal features 2 tones w/200Hz shift
                        using baud rates of 100 or 200 fitting into a 500Hz
                        channel. Pactor II is a half-duplex synchronous ARQ
                        system and designed to be backward compatible with the
                        older Pactor Level I protocol. The system can handle
                        raw 8 bit data and ASCII compression. Depending on band
                        conditions the data throughput can be increased by
                        changing the modulation form used. Maximum throughput
                        is 800 bps. Pactor Level II is operational in Europe
                        and is in the manufacturing stage in the US.

                          format                                 baud rate
                          -------                                ---------
                            DBPSK   Differential Binary PSK      200 bps
                            DQPSK   Differential Quad PSK        400 bps
                           8-DPSK   8-phase Differential PSK     600 bps
                          16-DPSK   16-phase Differential PSK    800 bps

1-C. PACKET-like signals or ASYNCHRONOUS DATA BLOCK signals. 

  While packet signals are a non-continuous signal much like SITOR-A their 
  sound is totally different from the regular chirp, chirp sound of SITOR-A. 
  These signals do not have the regular cadence of SITOR-A but have more of 
  a long duration burst sound.

        HC-ARQ          Haegelin-Cryptos simplex ARQ, a mode used by UN and
                        Red Cross services but these organizations have been
                        making a switch to PACTOR in recent years with very
                        few loggings in 95/96. This asynchronous system uses 
                        a packet like protocol with no defined timing and 
                        supports packet/block sizes of 38, 68 and 188 ITA2 
                        characters but always runs at 240 bd.

        PACKET          A mode used to allow data communications between PCs
                        and dumb terminals. This system is typically used by
                        radio amateurs, and to a lesser degree, United Nations
                        organizations. Incompatible versions also exist and are
                        in use by quasi-governmental organizations such as
                        ICRC, UNHCR or IFRB. Typically the AX.25 protocol in-
                        corporates a modified CRC. On HF there are a few items
                        to note;

            AX.25       Typically 300 bd on SW. Data is arranged in packets of
                        up to 256 bytes of 8 bit ASCII data. Each packet con-
                        tains a 1 byte start flag, 3 byte address field, 1 byte
                        control field, 0-256 bytes of data, 2 byte CRC and
                        finally a 1 byte end flag. Packets are transmitted with
                        no fixed timing. See the latest specification published
                        by the American Radio Relay League (ARRL) for complete
                        details on this system. There is also some 1200 baud 
                        PSK work done in the 10 meter ham band.

                        Automatic Packet Reporting System or APRS, is an appli-
                        cation that runs "on top of" AX.25. It was invented by
                        Bob Bruninga WA4APR that utilizes GPS data to plot a 
                        packet station's location on a map of a given region,
                        city, state, or even country. Due to the graphics 
                        involved, units like the M8000 will not read this data;
                        however, units like the PK232 can read it with the use 
                        of special software. Signals utilizing this mode are 
                        found in the 40 and 30 meter bands (for example) 
                        utilizing 'gateways' into 2 meters.

        CLOVER          A system originally developed by Ray Petit, W7GMH, and
                        now marketed by HAL Communications. The original modem
                        was named CLOVER-I, the latest DSP based modem is 
                        named CLOVER-II. It sounds like a "canary" when trans-
                        mitting. A signal consists of a 1s burst + a long 20s 
                        data transmission. Clovers key characteristics are band-
                        width efficiency with high error-corrected data rates. 
                        Clover adapts to conditions by constantly monitoring 
                        the received signal. Parameters which can affect quality
                        and reliability of the transmission such as block data
                        errors, phase dispersion, frequency offset, and signal
                        to noise ratio are monitored. Based on this monitoring,
                        Clover determines the best modulation scheme to use. 
                        Clover supports the following formats:

                          format                                 baud rate
                          ------                                 ---------
                           BPSM     4 pulse binary phase         125 bps
                           QPSM     4 pulse quad phase           250 bps
                           8PSM     4 pulse 8 phase              375 bps
                          16PSM     4 pulse 16 phase             500 bps
                           8P2A     4 pulse 8 phase 2 amplitude  500 bps
                          16P4A     4 pulse 16 phase 4 amplitude 750 bps

                       Total band width for all modes is a narrow 500 Hz with
                       a symbol rate of 31.25. Also known as 500Hz-CLOVER.

        400Hz-CLOVER   This is regular DSP based CLOVER packed into a narrow 
                       400 Hz bandwidth. This form of CLOVER is proprietary to
                       GLOBE WIRELESS and was developed in cooperation with
                       HAL Communications for use in Maritime communications.
                       Also known as CLOVER-II or KFS-CLOVER. This form of
                       CLOVER cannot be demodulated with standard CLOVER boards
                       as the DSP programming, power requirements and memory
                       capacity of the board was redone to support the new
                       narrow bandwidth.

        CLOVER-2000    A commercial form of CLOVER developed by HAL Communi-
                       cations, now in beta test. Supports 4x the speed of 
                       standard CLOVER and uses a bandwidth of 2kHz. With the
                       doubling of tones HAL has effectively doubled the rate.
                       Symbol rate is now 62.50. The 8 tones that make up this
                       signal are spaced 250Hz and are both phase and amplitude
                       modulated. Maximum bit rate is 3000bps. BPSM, QPSM, 8PSM,
                       8P2A, and 16P4A with "auto-throttling" are supported. 
                       Data packets are long, about 4s in duration. Idle chirps
                       are short, about .3s in duration with about .8s between 
                       chirps. Also known as "8-tone CLOVER", Q-CLOVER, or 

                          format                                  rate
                          ------                                  ---------
                           BPSM     8 pulse binary phase           500 bps
                           QPSM     8 pulse quad phase            1000 bps
                           8PSM     8 pulse 8 phase               1500 bps
                           8P2A     8 pulse 8 phase 2 amplitude   2000 bps
                          16P4A     8 pulse 16 phase 2 amplitude  3000 bps

        MERLIN/RS-ARQ/  A packet-like system running at 225bd with a shift of 
        packet          170Hz is believed to be another MERLIN/RS-ARQ variant,
                        its actual designation is unknown at this time.

1-D. MULTI-TONE signals/MFSK systems. 

  These signals are distinctive in how they sound. A rapid succession of tones,
  almost music-like in quality is their main feature. A sophisticated decoder 
  and a rock steady receiver is needed to process these signals.

        PICCOLO         Originally developed in 1957 in Great Britain at the
        MK6/MK10        Diplomatic Wireless Service or as it is known today the
                        Communication Engineering Department of the British
                        Foreign and Commonwealth Office (FCO). The original
                        system was a 32 tone system and the development team
                        was lead by J.D.Ralphs. 

                        There is a 6 tone system (MK6) using ITA2 and a 12 tone
                        system (also MK6) using ASCII/ITA5 but the 6 tone system
                        is the more common. The 6 tone system is used mainly by
                        the British Gov., Australian Gov. stations and Chilean
                        Military. The 12 tone system is used mainly by the
                        British Gov.

                        Both of the above systems normally run at 20bd but a
                        40bd, double speed variant, known as PICCOLO MK10 has 
                        been reported in use by British Gov. PICCOLO MK10 uses
                        6 tones, a special alphabet and different standby 
                        tones. Both 20bd systems can still be found on the air
                        and the modern MK6 unit is manufactured by RACAL. The
                        40bd system is rarely found at this time. Reference the
                        Klingenfuss RadioTeletype Code Manual 13th Edition for
                        the tone pairs and PICCOLO MK6 alphabet.

                        For tuning purposes on a 6 tone PICCOLO MK6 signal, 
                        zero between tones 3 and 4, on a 12 tone PICCOLO signal
                        zero between tones 6 and 7. A PICCOLO signal only has a
                        20Hz shift between tones so precise tuning is important
                        and the ability to magnify a signal is a great feature.
                        Inexact tuning will induce translation errors.

        COQUELET        COQUELET Mk I is an asynchronous 13 tone ITA2 system 
                        used by French (possibly abandoned) and Belgian mil./
                        police.  COQUELET Mk II is a synchronous 8 tone ITA2
                        system used by Algerian Diplo and Customs.  COQUELET
                        Mk I is also referred to as COQ13. COQUELET Mk II is
                        also referred to as COQ8 and can use a fourth shift 
                        Arabic/Latin keyboard.

                        Also note that users of COQ8 seem to be using a hybrid
                        COQ8/COQ13 system (possible COQUELET Mk III?). It is
                        probable that this is COQ-82 or COQUELET-8 v2, a  
                        synchronous scrambled system (mentioned as being 
                        available on Wavecoms W41PC/W4100DSP) used on the 
                        Algerian Diplo links. This system is capable of recog-
                        nizing either Latin or Arabic keyboards and can switch
                        accordingly. The system has a distinctive 13.3bd pre-
                        amble with a row of 'j's. This system is probably being
                        phased out.

                        COQ13 translates each 5 unit ITA-2 character into a 
                        sequence of 2 tones out of total of 12. A 13th tone 
                        represents the idle condition. The system takes each
                        character and breaks it into a 3 bit piece and a 2 bit
                        piece. The first 3 bits of the character are sent as 1
                        out of 8 possible tones (1-8) and the second 2 bits are
                        sent as 1 out of 4 possible tones (10-13). The idle 
                        tone, tone 9, is heard only during the idle or standby
                        condition. Each tone is 75 ms in length or one character
                        is 150 ms long giving the system a baud rate of 13.5.

                        COQ8 directly translates each character into a set of 
                        2 tones from a total set of 8 tones. The idle condition
                        used by this system is made up of tones 1 and 8 sent 
                        alternating.  Each tone has a duration of 37.5 ms or 
                        75 ms, giving an effective baud rate of 26.67 or 13.3.
                        Baud rates of 53.3 have also been monitored.

                        For tuning purposes on a 13 tone Coquelet signal, zero
                        on tone 9 during standby or between tone 8 and 10. On
                        an 8 tone Coquelet signal zero between tones 1 and 8,
                        these tones alternating is the idle condition.  In 
                        general, a Coquelet signal only has a 30Hz shift 
                        between tones so exact tuning is important and the 
                        ability to magnify a signal is a great feature. 
                        Reference Klingenfuss RadioTeletype Code Manual 13th
                        Edition for this systems tone mapping and alphabet.

        CROWD36         A Soviet MFSK system using 36 tones based on British
                        Piccolo MK1. CIS Diplo service is the main user with
                        suspected use by CIS Intel and Military services. This
                        system is found at 40 bd with a single tone lasting
                        25ms. Hand keyed traffic is usually 10 bd with a single
                        tone lasting 100ms. A spectrum analyzer will show the 
                        tones arranged in 3 distinct groups of 10+11+11 tones.
                        Tones are spaced 40Hz apart and tones 1, 12, 24 and 36
                        are rarely used so you are likely to see an 80Hz gap 
                        between groups. Each of the 32 tones represents one 
                        ITA2 character code. 

                        Also known as CIS/Russian Piccolo, URS multitone, CIS 
                        10-11-11 MFSK or CIS-36. As of this date there are NO
                        publicly available decoders for this system although
                        they do exist in the professional market. Some decoders
                        available NOW, possibly Wavecom and definitely Hoka, 
                        provide tools that can be used to demodulate the tones
                        and from there derive a character set. One such method
                        is covered below.

                        ITU documents have listed 4 different kinds of CROWD36
                        that vary with tone duration and baud speed. The '*'
                        entries below are commonly heard.

                                              +----------- tone duration (ms)
                                              |   +------- shift between tones
                                              |   |   +--- tones present signal
                                              v   v   v
                          Russian Piccolo 1   25  40  34   * 40bd
                                          2   25  10  34
                                          3  100  40  34   * 10bd
                                          4  100  10  34    

                        A few distinct patterns can be detected in a CROWD36
                        signal: selcal, idling and sending traffic. Selcal
                        and idling are a series of 5 tones repeated in the
                        same pattern. Traffic mode is most commonly, but not
                        always, found as 40bd encrypted and many times operator
                        traffic can be found in the clear at 10bd. Start-up
                        and sign-off are usually 10bd and hand keyed.

                        Using a Hoka Code30 V2.5 (US), select the "def general
                        multitone" from the demodulators menu. Settings are
                        36 tones, 40Hz spacing and 40.1bd. This will produce
                        output consisting of the raw tone sequences. Keep in
                        mind that 10bd operator traffic will appear as a 
                        sequence of 4 repeated characters.

                        To correctly zero a CROWD36 signal is difficult. The
                        signal is asymmetric so don't use the center of the
                        middle tone group. Tones are only shifted by 40Hz and 
                        tuning errors as small as +-5Hz will start to induce 

                        From the raw tone sequences use the table in Table 5-J
                        to map the tone number to character.

        Mazielka        A SELCAL system used by the "brotherhood" stations to 
                        wake up the receiving station operator outside normally
                        scheduled transmissions. Reported to be part of the
                        CROWD36 system outlined above. It is composed of 6 
                        tones out of a tone library of 13. See WUN Special 
                        Edition, V1.3, Apr '95 for a good explanation of the
                        system and its uses.

        MIL188          An 8 tone MFSK system running at 125 bps with users all
                        over the world including Europe, Africa, Asia, Middle
                        East and China. The only good way to distinguish users
                        is by monitoring the follow-on voice, cw, or other
                        modems. Tones are spaced 250Hz with tone frequencies of
                        750hz, 1000hz, 1250hz, 1500hz, 1750hz, 2000hz, 2250hz,
                        and 2500hz. Symbol duration is 8ms. This system looks
                        and sounds very much like TT2300b/TPLEX and is easy to
                        confuse but especially look for it preceding the 2400
                        bps NATO PSK traffic. Also known as MFSK188, NATO 
                        MIL188 or MIL-188-141 ALE. 

        TT2300b/TPLEX   An 8 tone, adaptive, synchronous system manufactured by
                        Thrane & Thrane of Denmark. The system runs at 100bd or
                        200bd using 8 bit ASCII with data throughput of 300 or
                        600bps. Primarily designed to be connected directly to
                        a serial port of a computer, the system features auto-
                        dial, subscriber addressing, electronic mail and can be
                        connected to a Fax machine. The full-duplex, error-
                        correcting (24 unit CRC) link protocol is completely 
                        transparent to any type of data coding. Used by French
                        Diplo, UK Civil Aviation Authority (National Air Traffic
                        System/NATS datalink, Prestwick/Reykjavik) and Algerian
                        oil companies. This may be logged in some commercial 
                        frequency lists as TT2300-ARQ, or TRA-2300. The manu-
                        facturer's name for the protocol/coding is TPLEX.

                        2 distinct modes have been monitored: tfc mode and an
                        idling sequence.

                        Frequencies to try: 5028.7, 5109.7, 7716.7, 7719.7.
                        8 tones, 200Hz spacing, ACF=8

        MERLIN/ALIS-2/  This is the 240 bd 8 tone burst ARQ mode used in the
        RS-ARQ          Rohde & Schwarz MERLIN modem. When the system is found
                        in the 7 tone mode it is in ISS mode, the IRS mode
                        uses an 8 tone signal. Both will be measured as 240 bd
                        (720 bits/sec) with tones shifted by 240Hz. Character
                        set can be ITA2 or ASCII with 8 bit ASCII being the
                        most common. The label ALIS-2 first appeared in the
                        Klingenfuss 14th Ed. Utility Guide. Reference the 
                        MERLIN/ALIS note above on naming.

                        Turkish, German and Italian Diplo stations are the
                        most commonly found users. The Italian Diplo stations
                        seem to favor the 5 bit (ITA2) mode. Turkish Diplo 
                        stations have been found using the 8 bit mode for all
                        Monitoring tip:
                        Its been discovered that all 8 tone channels have ALIS
                        (228.7bd) 2kHz below. So if you hear an ALIS procedure
                        in progress on a frequency it's worth waiting to see if
                        8 tone traffic appears 2kHz higher soon after.

                        See section 1-B for ALIS and section 1-K for a packet-
                        like MERLIN system.

        LINK-11         A US Military/NATO 40 DPSK synchronous system using 16
                        tones (1 doppler tone + 14 data + 1 sync tone), the 
                        14 data tones are 4-PSK modulated and spaced every 110
                        Hz (935Hz to 2585Hz w/doppler tone at 605Hz). The sync
                        tone is 2-PSK modulated. Typical rates are 1364b/s or
                        2250b/s. This is a ground wave only system, so a signal
                        received via HF will be nearly impossible to decode 
                        because the ionosphere messes up the phase. Klingenfuss
                        indicates a baud rate 2400. See MIL-STD-188-203-1A.
                        Also known as TADIL-A or "alligator". Largest man-
                        ufacturer of LINK-11 equipment is Rockwell-Collins.
                        See also LINK-11 LESW in section 1-A.

        MS5             This is the Russian (Soviet) 12 tone Vocoder system
                        with each channel QPSK modulated at 100 symbols/sec.
                        Each tone has a shift of 200Hz and spans a frequency 
                        range of 700Hz to 2900Hz in the Lower Side Band. This 
                        system has a distinctive pilot tone (unmodulated) at 
                        3300Hz above a kHz point with unconfirmed reports of a
                        pilot tone at 3600Hz and has a maximum capacity of
                        4800 bits/s. Commonly logged in the UK.

        ANNEX 10        An ARINC HF SELCAL system with 16 tones.

        HARCO-39/Harris A 4 phase PSK system implemented per MIL-STD-188-110A,
        39-tone modem   appendix B. The system supports data rates of 75 to 
                        2400bps using 39 tones spread from 675Hz to 2812.5Hz 
                        with a spacing of 56.25Hz. 1 doppler tone can be found
                        at 393.75Hz. Block interleaving with up to 12s delay is
                        supported. This modem has been implemented in the 
                        Harris RF-3466A and has been referred to as the Harris
                        39-tone modem in postings or HARCO-39 in Klingenfuss 
                        frequency lists. Check out 6712.0 (Croughton) or 
                        11223.0, 11183.0 or 5720kHz. 

                        A 39-tone modem sounds like noise, so as you tune across
                        this signal an S meter will rise and fall. It sounds
                        very much like tuning a noisy frequency.

        CODAN modem     A commercial unit from Codan Pty of Australia currently
                        used in Australia and Africa by the United Nations, aid
                        agencies and various public authorities. The modem uses
                        16 tones and are QPSK modulated. The tones range from
                        656.25Hz to 2343.75Hz with a tone shift of 112.5Hz and
                        runs at 2400bps. The modem is fully automatic and 
                        supports compression and selective calling. No ALE is
                        used for link setup but a simple beacon call and audio
                        analysis on the return signal is all thats needed. This
                        modem is mainly used in mobile networks.

                        The modem has a few distinctive sounds to it. A 2 sec.
                        "squawk" is used to realign channels. If you hear short
                        bursts then the modem is idling.

1-E. FAX-like signals. 

  These signals are used for transmitting pictures, mostly marine weather 
  maps over the airwaves and make a distinctive scratch-like sound. Press-FAX
  can still be found but with less frequency as Press services continue to 
  move to satellite.

        HELLSCHREIBER   FAX-like mode in that it was used to send pictures but
                        works more like common RTTY. The Siemans systems listed
                        below used start/stop signalling (FSK) and the Field 
                        HELL unit was semi-synchronous. The system was used by
                        the Chinese Internal Press up until about 1993 but is 
                        now used by European amateurs on 80m and 40m. 

                        A couple of different machines were available:

                                +----------------------------------  Name
                                |        +-------------------------  Paper width
                                |        |    +--------------------  chars/min
                                |        |    |     +--------------  chars/sec
                                |        |    |     |    +---------  baud rate
                                |        |    |     |    |     +---  bandwidth
                                v        v    v     v    v     v     tone freq
                        Siemans GL72   |9.5mm|367.8|6.13|300  | 600Hz| 1000Hz
                        Field HELL     | 15mm|150  |2.5 |122.5| 360Hz|  900Hz
                        Siemans HELL 80| 15mm|300  |5.0 |300  | 900Hz| 1260Hz

        FAX             A picture transmission mode used by weather (meteo),
                        some Press and less often, amateurs. Pictures are sent
                        line by line and to correctly receive a picture you
                        must, at most, have the drum speeds (RPM) in sync. Usual
                        RPM values are 60, 90, 120, 240. Less important is the
                        IOC (Incidence of Cooperation). Usual values for IOC
                        are 288, 352, 576. For the picture to be received as
                        it was sent both RPM and IOC should match the senders
                        RPM and IOC. It is true that FAX use is in decline and
                        will continue to do so in the near future.  Common
                        forms found:

                              Press FAX     60-240RPM   IOC 352,576
                              Weather FAX   60-240RPM   IOC 288,576

            'Encrypted' FAX

                        A recent wrinkle now appearing in the declining FAX
                        signal arena is the introduction of 'encrypted' FAX
                        transmissions. USAF Puerto Rico and Tokyo Radio JJC
                        have been using this FAX mode. At this time there are
                        no decoders that are able to handle this kind of FAX
                        transmission (although JCC will apparently sell you

                        As for the signal itself, the start, stop, and phasing
                        signals appear to be normal but the picture data seems
                        to use some sort of modified code. Current speculation
                        suggests Huffman encoding or a Modified Read Code with
                        FAX lines only including the pixels changed from the 
                        previous line.

                        Reference Klingenfuss Guide to Facsimile Stations for
                        a discussion of FAX theory and examples.

1-F. SSTV - Slow Scan TV. 

  A picture transmission mode developed and used by the Amateur community. 
  While these signals are FAX-like in function they do not possess the 
  scratching quality of the FAX signal. The sound of an SSTV signal is more 
  tonal in its composition. I do not believe that each mode can be 
  distinguished by ear. 

  Currently the most popular mode found on the airwaves in North America is 
  Scottie S1, followed less frequently by Scottie S2, Robot 36 and 72 and 
  finally some Martin M1. Europe seems to be mostly Martin M1. 

  Frequencies to check: 14230 seems to be the most popular. Also check 3730,
  7040, 21340 and 28680.

  There are also a few newer experimental modes available from Pasokon,
  ProSkan, WinPixPro and Acorn. They are not widely available yet.

  As the table below shows there are lots of modes to choose from with very
  little in the way of a standard but the basic "standard" transfers 1 line
  in 8s and uses a resolution of 120x120. The sync tone used is 1200Hz, the
  Black tone is 1500Hz and the White tone is 2300Hz.

  SSTV modes

          +------------------------------------------- Mode
          |           +------------------------------- LinexPixel Resolution
          |           |         +--------------------- Color/RBG seq. or B/W
          |           |         |      +-------------- Time (sec)
          v           v         v      v               Comments
   AVT 24          | 128x128 | Color |  24 | There is a 5s digital header and
       90          | 240x320 | Color |  90 | there is no horizontal sync
       94          | 200x320 | Color |  94 |
       125         |     400 | B/W   | 125 |
       188         | 320x400 | Color | 188 |
   Wraase SC-1 24  | 128x128 | Color |  24 | -top 8 lines are grey scale
          SC-1 48  | 256x128 | Color |  48 | -top 16 lines are grey scale
          SC-1 96  | 256x256 | Color |  96 | -top 16 lines are grey scale
          SC-2 30  |     128 | R-B-G |  30 |
          SC-2 60  |     256 | R-B-G |  60 |
          SC-2 120 |     256 | R-B-G | 120 |
          SC-2 180 |     256 | R-B-G | 180 |
   Scottie S1      | 256x320 | G-B-R | 110 | -top 16 lines are grey scale
           S2      | 256x320 | G-B-R |  71 | -top 16 lines are grey scale
           S3      |     120 | G-B-R |  55 | -top 8 lines are grey scale
           S4      |     120 | G-B-R |  36 | -top 8 lines are grey scale
           DX      |     240 | G-B-R | 269 | -top 16 lines are grey scale
   ScanMate1       | 512x310 | Color | 391 |
   ScanMate2       | 512x310 | Color | 261 |
   ScanMate DX     | 256x256 | Color | 269 |
   Martin M1       | 256x320 | G-B-R | 114 | -top 16 lines are grey scale
          M2       | 256x320 | G-B-R |  58 | -top 16 lines are grey scale
          M3       | 128x128 | G-B-R |  57 | -top 8 lines are grey scale
          M4       | 128x128 | G-B-R |  29 | -top 8 lines are grey scale
   Robot 12        | 120x128 | Y-C   |  12 | Color is sent as Luminance and 
         24        | 256x256 | Y-C   |  24 | Chrominance
         36        | 256x256 | Y-C   |  36 |
         72        | 256x256 | Y-C   |  72 |
         8         | 120x128 | B/W   |   8 | Not a true B/W mode. Green element
         12        | 120x320 | B/W   |  12 | sent as B/W image
         24        | 240x320 | B/W   |  24 |
         36        | 240x320 | B/W   |  36 |
   SC-1 and SC-2 were developed by Volker Wraase in Kiel, Germany.
   Martin was developed by Martin H. Emmerson, G3OQD/England.
   Scottie was developed by E.T.J. Murpy, GM3SBC/Scotland.
   Robot was developed by Robot Research.

  SSTV VIS code
  With the introduction of Robot 1200C, Robot Research introduced the VIS
  code, which is used to indicate the speed and mode at the beginning of the 
  transmission. The VIS code, when decoded by the receiving station, will
  let the receiver automatically set the necessary parameters for proper
  reception. The VIS code is sent as part of the vertical sync pulse and
  is 10 bits long lasting 10*30ms. The start and stop bits are represented as
  a 1200Hz tone with the remaining 8 bits (including 1 even parity bit) left
  for encoding information. This breaks down as 1 30ms start bit at 1200Hz,
  7 data bits, each 30ms, sent Lowest Significant Byte (LSB) first (logical
  '1' is transmitted as 1100Hz, logical '0' is transmitted as 1300Hz). 1 30ms
  even parity bit and 1 30ms stop bit as 1200Hz. The table is fairly extensive
  so for now reference the following www page(s): (valid as of 1/19/96)    (valid as of 1/19/96)

  These signals are distinctive in sound in that they are continuous and 
  possess a trilling quality. The sound of an idling signal is slightly 
  different from a signal actively sending traffic. Many signals idle for 
  long periods of time and send very little traffic, i.e. ARQ-E, ARQ-E3, or 
  ARQ-M2. They can be found all over the shortwave spectrum. Other signals 
  have a short idling phase and move directly into traffic and then terminate, 

        BEE/36-50       A Russian Navy and Polish Mil./Intel Svc. synchronous 
                        bit stream commonly found in Europe but can be heard 
                        in the US, traffic is most often found running at 50bd
                        but some 100bd signals have been found as well. The 
                        system has no apparent ACF (ACF=0) and then idles with 
                        36 bd (ACF=2). As the traffic switches from 36bd to 
                        50bd a preamble can be detected running with ACF=70. 
                        The system appears to be synchronous with 1 stop bit 
                        and common shifts of 85Hz, 125Hz, 250Hz and sometimes 
                        500Hz having been recorded. In between, or at the end 
                        of messages, FSK CW has been heard using the callsign 
                        RDL. The CIS name for this system is T600.

        81-81/81-29     A Russian/URS Military system with some speculation 
                        that a number of ex-Eastern Bloc countries might also
                        make use of this system. This signal is mainly 81 bd, 
                        pseudo random, one or two characters, 12 bits, usually
                        encrypted. Operator chatter can sometimes be found in 
                        the clear using Baudot w/Cyrillic M2 alphabet. It is 
                        mainly a 2 ch system but there is a 40.5 bd signal that
                        is a 1 ch variant. Most commonly found baud rates are 
                        36.5, 40.5 for the 1 ch version and 73 and 81 for the 
                        2 ch version. 

                        Code30 US Ver. 2.5 includes an 81-81 module but no
                        traffic has been recorded yet. Speculation is that this
                        older 81-81 system, as defined above, is no longer in 
                        use and that the newer 81-81 system heard NOW is more 
                        likely to be derived from the CIS-14 or CIS-27 system 

                        Reports from the Logs indicate a few different users
                        of this system. The shift pattern seems to hold for
                        the other baud rates used by this system.

                               Shift           Common User
                               --------------  -----------------
                               125             Navy
                               500             Railway Authority
                               200,250,500,    Military

        ARS-GUARD       A Saudi National Guard synchronous FEC system, running
                        at 125 bd and 170Hz shift (ACF=48 or 96). Check out the
                        following frequencies:7672.5, 7869.5, 12257.5, 12357.5,
                        12362.6, or 12457.5. Maybe known as SAUD-NAT.

        ARQ-E           A very common single channel duplex ARQ system, made by
                        Siemens, used by French Military Forces, Italian Diplo
                        stations and the German Gov., typically 48, 64, 72, 86,
                        96, 144, 192 or 288bd but the system can be adjusted 
                        with different gear variants to support user require-
                        ments. ARQ-E can also appear in VFT. Some of those baud
                        rates and users are listed below:

                             Baud      Common/Suspected User
                             -----     ----------------------------------------
                              46.1     Egypt-Jordan Air coordination (VFT)
                              85.7     encrypt tfc, most likely Mossad or BNDVB
                             184.6     FF circuit used by RFFXQA Sarajevo, BIH

                        Also known as ARQ-1000D.

        ARQ-E3          Another very common single channel duplex ARQ system 
                        used by French Military Forces, typically 48, 64, 72,
                        86, 96, 100, 144 or 192 bd.

        ARQ-M2          A commonly found full duplex, synchronous, time division
                        multiplex ARQ system w/2 data channels, typically using
                        87, 96 or 200 bd. French Military Forces are the most 
                        commonly found user and this system can idle for long
                        periods of time with no traffic. An odd baud rate of
                        128.5 has been found on a number of circuits between
                        Papeete, Tahiti and Mururoa. This system comes in 2 
                        flavors: one is defined by the old CCIR 242 Recom-
                        mendation and the other is defined by the newer CCIR
                        342 Recommendation. Both forms can still be found. Also
                        known as TDM, ARQ-28, TDM-2, TDM-242, TDM-342 or 96-TDM. 
                        See Section 4 for Recommendation differences.

        ARQ-M4          A rarely found full duplex, synchronous, time division
                        multiplex ARQ w/4 data channels, typically using 87,
                        96, 192 or 200 bd. This system had been used by Chinese,
                        Vietnamese and Spanish embassies. Loggings within the
                        past year indicate use by some French Military Forces
                        stations. This system can also idle for long periods of
                        time with no traffic.  This system also comes in 2 
                        flavors as defined by the same recommendations as 
                        ARQ-M2. Also known as ARQ-56, TDM-4, TDM-242, TDM-342
                        or 192-TDM. See Section 4 for Recommendation differences

        ARQ-N           A single channel duplex ARQ system used by Italian 
                        Diplo services, typically using 72, 96, 144 or 192 bd.
                        This system is related to ARQ-E but does not inverse
                        any bits.

        AUTOSPEC        A FEC system once used by British coastal stations to
                        communicate with North Sea oil rigs, typically ran with
                        baud rates of 62.3, 68.5 or 102.7 bd. This has probably 
                        been replaced with microwave. Also known as Autospec-
                        bauer or Bauer and has been referred to as Autospec 
                        Mk1. No loggings have been recorded in the previous 
                        year. See SPREAD.

        SPREAD          A FEC system, used (formerly?) by Romanian diplo
                        stations, using the Bauer code used by Autospec, with
                        characters spread over a large time span, designed to
                        reduce burst and fading errors. SPREAD-51 has been
                        known to be used by Brazilian Navy and shore stations
                        but no loggings have been noted for at least 4 years.
                        SPREAD-11 and SPREAD-21 have not been logged recently.
                        Typically 68.5, 102.7 or 137 bd. Also known as SPREAD
                        -11, SPREAD-21 or SPREAD-51 depending on data spread
                        in effect. SPREAD is Autospec Mk2. When a station
                        sending SPREAD is idling it cannot be distinguished
                        from AUTOSPEC. The 2 systems can only be identified
                        when sending traffic.

        CIS             A general term defining a few systems used by Russian
                        organizations, they are distinguished from each other
                        by the bit lengths used: 11, 14 or 27 bits. CIS-11 and
                        CIS-14 are reported to be decodeable using the Wavecom
                        4100DSP or the W41PC and Hoka Code 30.

                        * CIS-11 is a single channel duplex ARQ system used by
                          Russian meteorological stations running at 100.05bd
                          (according to Wavecom) or 50, 100, 150, 200 and 300
                          (according to Klingenfuss RadioTeletype Code Manual
                          13th Edition). This system uses the Cyrillic M2
                          alphabet in an 11bit word, 5 bits for the M2 word
                          (bits reversed), 2 bit system state and 4 bits error
                          correction. CIS-11 is also known as TORG-11 (system
                          has not been used by Russians for years).

                        * CIS-14 is reported to be used by Russian PTT stations
                          on links to the former republics. CIS-14 is a two
                          channel duplex ARQ system running at 96-192bd 
                          (according to Wavecom) but the 13th Edition of the
                          Code Manual lists a whole host of baud rates: 42.1, 
                          47.5, 48, 50, 70.5, 72, 83.3, 84.21, 94.11, 96, 100,
                          144, 200 and 288 bd. This system has a 14 bit frame
                          size with a 2 bit channel state, 2 M2 characters bit
                          interleaved and 2 bits error detection. CIS-14 is 
                          most commonly logged running with 96bd and most
                          traffic appears to be encrypted but at sign on you
                          might be able to find some operator chatter and
                          test tapes. You may find CIS-14 referenced by the
                          name AMOR or AMOR 96 (unofficial name used by some
                          NATO members).
                        * CIS-27 is currently defined as a 50 and 100bd system
                          reported in 3 lines in the Radioteletype Code Manual,
                          13th Edition. 1 partial logging found in the WUN logs
                          with no mention of this system made in Wavecom or
                          Hoka documentation. Might best be listed in the
                          Mystery section.

        DGPS            Another type of DGPS is the commonly found 100bd or
                        300bd MSK signal. MSK sounds like SITOR-B and is 
                        usually transmitted from beacons in the 285-325kHz
                        region with an ACF=10. The information transmitted is
                        real-time differential corrections in RTCM SC104 V2.1
                        format. There are commercial companies providing DGPS
                        service and their data will probably be encrypted. See
                        Utility Roundup in WUN 2/1 (Jan '96) for a good writeup
                        on this signal and its users or section 1-J for the 
                        QPSK form of DGPS.

        DUP-FEC/        A new system appearing with the introduction of the
        DUP-FEC-2       Wavecom W41PC (DUP-FEC-2) and the new Klingenfuss Radio
                        Data Code book (DUP-FEC). No new signals found on the
                        air as of yet. The system runs at 125 or 250bd and
                        uses the ITA-2 or ITA-5 character set. This system is
                        an enhancement of the DUP-ARQ-2 system and has many

        FEC-A/FEC-100   A system used by Turkish and German Press also German,
                        French (P6Z etc), Serbian (DFZG) and Turkish (TAD) 
                        Diplo services, typically runs with 96, 144, 192 or 
                        288 bd and uses the ITA2-P alphabet. A fast baud rate
                        of 384 (192x2) has been found in use by MFA Paris, F 
                        and French Emb., Rou. Siemens is the manufacturer and
                        refers to this system as FEC-100 or FEC-100A. 

        GMDSS/DSC       Digital Selective Calling is a variation of Sitor-B,
                        100 baud 170 shift, but uses a special set of 127 
                        symbols with a 10 bit error correcting code. The 
                        system is defined in the ITU recommendation ITU-R 
                        M493-6. A DSC signal is short, about 6-7 seconds on
                        MF/HF and contains the following: station ID, priority,
                        station being called, frequency to use. This system is
                        used to establish the initial contact between ships and
                        shore stations using GMDSS.

                        DSC signals can be found the following frequencies: 
                        2187.5, 4207.5, 6312.0, 8414.5, 12577.0, 16804.5 (also
                        on VHF on Ch. 70 - 156.525 @ 1200bd). See Digital 
                        Review column in WUN newsletter Vol. 1, No.12 December,
                        1995 for a good writeup on GMDSS/DSC.

        HNG-FEC         A FEC system used by Hungarian Diplo services, typically
                        100.05 bd. This system uses a bit spread of 64 bits with
                        each new character starting at intervals of 15 bits.
                        See Klingenfuss RadioTeletype Code Manual 13th Edition 
                        for teleprinter alphabet used by this system.

        IRA-ARQ         An ARQ system used by the Bulgarian Diplo services,
                        typically 75, 100, 110, 150, 180, 200, 240, 300, 600
                        or 800bd. Max speed seems to be 1200bd. This system uses
                        an 11 bit character. A 10 bit variant has been noted 
                        but is rarely found. ACF is typically 55 during idle
                        with a rhythmic cadence to the signal sound. When 
                        sending traffic the ACF disappears and the sound 
                        intensifies to a steady buzz.

                        A tip for monitors is to remain on frequency with the
                        decoder set to ASCII/ITA-5 at the same speed that the
                        ARQ is sending. Once the transfer is complete, operator
                        chat often takes place in standard ASCII or BAUDOT. 

                        A note of caution when measuring this system with its
                        high baud rate. Some decoders are unable to measure
                        high baud rates accurately or because of some in built
                        maximum baud ceiling don't show the true baud rate. 
                        Hoka Code 3 has a maximum measurable baud rate of 
                        480bd and will display a baud rate of 272.73 for a 
                        600bd IRA-ARQ signal and 363.63 for an 800bd IRA-ARQ 
                        signal. The Hoka Code 30 also has the 480bd maximum
                        but word has it that this will be removed in a later
                        version. I have no comparison to offer concerning the
                        Wavecom unit(s) ability to measure high baud rate 
                        systems at this time.

        POL-ARQ         A single channel duplex ARQ system used by Polish and 
                        Italian Diplo services, typically at 100 bd but also
                        found less frequently at 200bd. This system uses the
                        CCIR 476-4 alphabet with same polarity retained. Can 
                        be easily confused with Sitor-B.

        RAC-ARQ/        Previously believed by the community at large to be a 
        MEROD           fabrication it has been revealed that the system 
                        actually exists. MEROD (Message Entry and Read Out
                        Device) is the commercial name for the Racal man-
                        ufactured equipment that uses the RAC-ARQ mode. This 
                        FEC system is documented to run at 150 and 267bd using
                        a "wide shift FSK". This system documented heavily in
                        the Radioteletype Code Manual 13th Edition from
                        Klingenfuss with signal samples available on the 
                        Klingenfuss Modulation cassettes on track 38. Also
                        if you read the Wavecom W4100 glossy from the company
                        they list RAC-ARQ as an option but later glossies for
                        the W4100DSP and W41PC no longer list RAC-ARQ. Also
                        known as RACAL-ARQ.

        ROU-FEC         A FEC system used by Rumanian Diplo services, typically
                        164.48 or 218.3 bd. Signals can be encrypted, in the
                        clear or bit-masked (have been known to use 10, 15, 24
                        or 31). This system has a bit spread of 128 bits with
                        each new character starting every 16 bits. This system
                        had been referred to as SAU-FEC in the past and renamed
                        to RUM-FEC by Klingenfuss Publications. Wavecom still
                        refers to the system as RUM-FEC in their documents.

        SITOR-B         A FEC system used by Marine Information services and
                        the Amateur Radio community, typically 100 bd but an
                        odd baud rate of 109.4 has also been monitored origin-
                        ating from Cuba. Also known as FEC or AMTOR.

        SI-FEC/FEC-S    A Siemens FEC system used by Austrian and Indonesian 
                        Diplo services, typically 96, 192 or 200 bd using the
                        ITA-3 alphabet. Also known as FEC-S, FEC1000 Simplex
                        or FEC 1000S. During idle mode this system is the
                        same as CCIR 242 (ARQ-M2).

        TORG-10/11      A Soviet 2 frequency duplex ARQ system used to transmit
                        Meteo data using 10/11 bit blocks of ITA2 coded data 
                        plus error correction. Typically running 100 bd, 500Hz
                        shift. TORG-11 is also known as CIS-11 and has not been
                        used by the Russians for years.

        NATO-75         Various NATO members have equipment which generates 
        NATO-100        75bd or (more rarely) 100bd RTTY with a variety of 
                        shifts from 85Hz to 850Hz. Within the service, these
                        systems are usually known as RATT or CRATT (Crypto RAdio
                        TeleType). We also have indications of the system being
                        known as "Beaver" (US) or Link 4, although this is 
                        unconfirmed at present.  

                        Traffic can often be recognized by twice repeated header
                        block of 256 bits which shows an ACF of 64, and by a 
                        period of sustained reversals between "messages". The
                        remainder of traffic is pseudo-random.  

                        Such a system can be found permanently on 4711, 6702,
                        and 11264kHz. We believe that this system is closely 
                        related to the Royal Navy's common "Fleet Broadcast" 
                        75bd or 100bd system which has a message preamble of 
                        16 RYs and VMGTCNJBH in Baudot before switching to 
                        encryption. A similar system has been reported in use
                        by the French with a synchronization string of VYMGTCN.
                        Reference Digital Review column in WUN V1,#1,2/95 and
                        WUN V1,#11,11/95.


  These signals sound like the continuous bit stream signals but with a subtle 
  cadence difference to them. They are most often encountered sending traffic.

        BAUDOT          A common signal used by the Amateur community, many
                        military and government services, typically 50, 75 or
                        100 bd. Inversion is possible but not frequently 
                        encountered on the data bits, giving 2^5 (32) possible
                        arrangements. Watch for stations sending BAUDOT but 
                        using different character sets such as Arabic ATU-70,
                        4th Shift Arabic ATU-80 or Cyrillic, they might look
                        like scrambled transmissions at first glance. Reference
                        the Klingenfuss RadioTeletype Code Manual 13th Edition
                        for some good examples and partial dictionaries. Also 
                        known as RTTY or ITA2.

        ASCII           A rarely found signal used by the amateur community
                        typically 110, or 300 bd but has been tested in recent
                        times by VOA. Amateur station W1AW still transmits
                        ASCII bulletins. Many times Bulgarian IRA-ARQ operator
                        traffic can be decoded using ASCII. Also known as ITA5
                        or IRA.

        BAUDOT/F7BBN    This is a 2 channel simplex asynchronous BAUDOT signal
                        also referenced as TWINPLEX. Its form, according to CCIR 
                        Recommendation 346-1, is: "4 Frequency diplex systems"
                        (Dusseldorf, 1990). Hoka Code 3 and Code 30 have a
                        module for this labeled as: "Baudot F7BBN, 2ch ITA-2 
                        RTTY". This is a 2 channel 4 tone diplex asynchronous
                        signal usually consisting of 2 channels of ITA-2 baudot
                        running at the same speed (or according to Rec. 346-1
                        1 channel baudot/1 channel morse code). According to 
                        the recommendation both channels are often scrambled
                        and no loggings of this form have been found to date.

1-I. MULTI-CHANNEL/BUZZSAW like signals. 

  These signals are obnoxious in the way they sound. They have a very harsh 
  buzz-like quality. Tough to decode because many signals can be transmitted 
  together and even interleaved.  Signal Diversity is often used - defined as 
  all channels sending the same traffic but shifted in frequency and shifted 
  in time. The receiving equipment combines the channels into a single channel
  if 'X' channels agree. Many times the channels are encrypted. A stand alone
  spectrum analyzer or one incorporated within the decoder can be a great help
  in identifying the signal arrangement. Hoka Code 3 and Code 30 units have a 
  spectrum analyzer feature. Code 30 has the added ability to target an in-
  dividual channel for decoding. Wavecom 4100, 4050 and Universal M8000 units
  also include a spectrum analyzer or spectrum display feature.

  VFT or Voice Frequency Telegraphy is a general term used to define many 
  kinds of multi-channel signals used by British Military, Canadian Military,
  US Military and other government institutions. Many configurations are 
  possible. Also known as FDM or WTK (a misnomer, see MULCAST below).

  Reference WUN V2#5, May '96, Digital Review for a good article on VFT.

* BR6028      6028 Series Diversity is a commonly found VFT system using 7 
              channels of 45 bd to 100 bd baudot each with 170 Hz shift used by
              US and Canadian Military. Channels are shifted in time, with each
              channel delayed by 1 second and any channel with heavy inter-
              ference can be locked out causing the transmitter side to stop 
              using the interfered with channel. This accounts for those less 
              then 7 channel VFT's sometimes found. Also known as "BARRIE", 
              6028 or USA 7 channel modem.

              Note: channel numbering was selected arbitrarily 1234567, some
              documents show channel numbering as 3614752 which are the
              channels in time order.

                   +-------+------+------+-----+------+------+-- Baudot 45-100bd
                   |       |      |      |     |      |      |   7 ch diversity

    shift:         170    170    170    170   170    170    170
                  ++++   ++++   ++++   ++++  ++++   ++++   ++++
               $  M  S   M  S   M  S   M  S  M  S   M  S   M  S
               $  |  |   |  |   |  |   |  |  |  |   |  |   |  |
    |         ||   |    | |      ||     |   | |      ||     |   |         |
    f0         |   |   1000      |      |  2000      |      |  3000
               |   |      |      |      |     |      |      |
    offset:   560 850    1190   1530   1870  2210   2550   2890 
    channel:   P   1      2      3      4     5      6      7
    Note: the Pilot tone at 560kHz is an unmodulated tone.

              Belgian Diplo (MFA Brussels, Embassy Beirut, circuits to South
              Africa, South America and southern Europe) have been noted using
              what seems to be a modified BR6028 system. Configuration shows:

                            pilot tone, ch 1, NO ch 2, Ch 3 - 7

              Channel 2 never seems to be present. All channels carry 100bd/170
              Baudot delayed in time by 0.5 secs. This VFT form has been noted
              on the following frequencies: 11107, 14476 and 14904 most early
              mornings (06-08UTC).

                   +--------------+------+-----+------+------+-- Baudot 100bd
                   |              |      |     |      |      |   w/ch diversity

    shift:         170           170    170   170    170    170
                  ++++          ++++   ++++  ++++   ++++   ++++

               $  M  S          M  S   M  S  M  S   M  S   M  S
               $  |  |          |  |   |  |  |  |   |  |   |  |
    |         ||   |    |        ||     |   | |      ||     |   |         |
    f0         |   |   1000      |      |  2000      |      |  3000
               |   |             |      |     |      |      |
    offset:   560 850           1530   1870  2210   2550   2890 
    channel:   P   1             3      4     5      6      7

* MULCAST/    A system used by the US Military composed of 16 channels each 
  WTK170      with an 85 Hz shift spaced 170Hz. This system was used by the
              US Navy and has since disappeared from HF. Broadcasts have been
              monitored with 2 clear channels, Ch.14 ran 75bd weather from 
              KAWN and Ch.16 ran 50bd APN/UPI news. This arrangement is defined
              by CCITT R.39-1 and is Mode B in the Universal M7000 decoder.
              This system is also referred to as Weston Telegraph Keying 170
              (WTK170 or Marconi H5000).

   shift   85  85 85  85 85 85  85  85 85 85 85  85 85  85  85 85
           ++  ++ ++  ++ ++ ++  ++  ++ ++ ++ ++  ++ ++  ++  ++ ++

           MS  MS MS  MS MS MS  MS  MS MS MS MS  MS MS  MS  MS MS
           ||  || ||  || || ||  ||  || || || ||  || ||  ||  || ||
    |      |  ||  |   | ||  |   | | |  |  | ||   |  | | |   |  ||         |
    f0     |   |  |   |1000 |   |   |  |  |2000  |  |   |   |  3000
           |   |  |   |  |  |   |   |  |  |  |   |  |   |   |  |
   offset 382  | 722  | 1062|  1402 | 1742| 2082 | 2422 |  2762|
              552    892   1232    1572  1912   2252   2592   2932
   ch:     1   2  3   4  5  6    7  8  9  10 11  12 13  14  15 16

   Note: The above illustrated channels are spaced 170Hz - this does not
         convey well in an ascii representation.
   Note: There is also an 8 channel system called Weston Telegraph Keying 340
         (WTK340). 8 channels shifted 340Hz with 170Hz shift on each channel. 

  The following VFT signals are commonly found in use by the named users so the
  authors have assigned names for use as a starting point in future discussions.

  * RUS-144 - 3 channels of 144bd/200Hz FEC system, with each channel spaced by
              950Hz. The FEC system appears to be a synchronous system with no
              apparent ACF and is used by Russian PTTs. It has been noted on the
              following frequencies: 8077kHz (nighttime) and 14814kHz (daytime).
              It has also be noted in the past on 8063/14327.

                       +------------------+------------------+-- Unid-FEC 144bd
                       |                  |                  |

    shift:            200                200                200
                      +++                +++                +++
                      M S                M S                M S
                      | |                | |                | |
    |         |        ||         |       | |         |      |  |         |
    f0                 1000               |2000              | 3000
                       |                  |                  |
    offset:           950                1900               2850
    channel:           1                  2                  3

* FEC-101 -   (formerly labelled "3 ch FEC-100") 3 channels of FEC-100 are known
              to be in use by Israeli Military, German, Indian MFA and Serbian
              Diplomatic services. Usual channel speeds are 3 channels of 144,
              96 or 192bd with shifts between 80Hz and 170Hz. The 3ch 192bd/170
              Hz arrangement with a channel spacing of 680Hz is German Air Force
              (shown below). Also Indian MFA, Dehli has been using a 3ch VFT 
              with 96/170 and shifted 650Hz. This system a 3ch FDM and TDM 
              system with each channel delayed in relation to the others and
              spaced apart to reduce any intermodulation.

                   +-----------+-----------+-------------------- FEC-100 96,
                   |           |           |                     144 or 192bd

    shift:       170         170         170
                 +++         +++         +++

                 M S         M S         M S
                 | |         | |         | |
    |         |   |     |     |   |       | |         |         |         |
    f0            |    1000   |           |2000                3000
                  |           |           |
    offset:      680         1280        1900
    channel:      1           2           3

    A more classic arrangement is illustrated below:

              +-------------------------+---------------+------- FEC-100
              |                         |               | 

    shift:   170                       170             170
             +++                       +++             +++

             M S                       M S             M S
             | |                       | |             | |
    |         | |       |         |     |   |         | |       |         |
    f0          |      1000             |  2000         |      3000
                |                       |               |
    offset:    595                     1785            2635
    chan:       1                       2               3

* MOI-VFT - The German Ministry of Information (MOI) and police use a multi-
              channel VFT comprising 72 or 96bd, 80Hz shift ARQ-E on their 
              intercity links. Commonly heard below 5MHz in Europe. The
              channels for the Bonn-Stuttgart and Bonn-Hamburg links is 
              shown below:

                  +---------------+----------------------------- ARQ-E 72bd
                  |               |     +-------------+-------+- ARQ-E 96bd
                  |               |     |             |       |
shift:            80              80    80            80      80
                  ++              ++    ++            ++      ++

                  MS              MS    MS            MS      MS
                  ||              ||    ||            ||      ||
    |         |   |     |         |     |   |         |       | |         |
    f0            |    1000       |     |  2000       |       |3000
                  |               |     |             |       |
offset:          720             1500  1800          2510    2900
channel:          1               2     3             4       5

* 3 ch 150 FSK - The German Navy, primarily Wilhelmshaven (DHJ59 and warships)
               has been noted using a configuration of 3 channels running a 
               150bd 170Hz shift FSK system with each channel spaced about 680
               Hz to 700Hz. The 150bd FSK signals are Unid.

                           +-------------+-------------+-------- Unid-FSK 150bd
                           |             |             |

    shift:                170           170           170 
                         ++++          ++++          ++++

                         M  S          M  S          M  S
                         |  |          |  |          |  |
    |         |         | |       |     |   |         |         |         |
    f0                 1000             |  2000       |        3000
                          |             |             |
    offset:              1190          1870          2550
    channel:              1             2             3
* 3 ch Piccolo - British Military 6-tone Piccolo system with 2, 3 or 4 channels 
               have been noted. The traffic channels are usually found sending
               bitstream encrypted traffic and the engineers channel idles or
               sends plain text operator chatter. The following channel offsets
               (measured from the f0 carrier point) are usually found at: 
               +0.51kHz, +0.91kHz, +1.31kHz and +1.91kHz.

              +-------+-------+-------+------------------------- 6-tone Piccolo
              |       |       |       |

    shift:    ++      ++      ++      ++ 

              ||      ||      ||      ||
    |         |       | |     |   |   |     |         |         |         |
    f0        |       |1000   |       |    2000                3000
              |       |       |       |
    offset:  510     910     1310    1910
    channel:  1       2       3       4
    Note: channel 1 is engineers channel 

* UK Military 8 ch VFT - A common UK (DCN) interleaved VFT. Most channels
               carry RYI type traffic but channel 1 carries occasional engineer
               exchanges. See WUN newsletter, issue 2.9 for further comments.
               This is also known as British HL13 (TA5).

          +----+---------+---+---------+---+--------+---+----- Baudot 50/340
          |    |         |   |         |   |        |   |      ARQ-M2 96/340

shift:   340  340       340 340       340 340      340 340
            +-----+      +------+      +-----+      +------+
        +---|--+  |   +--|--+   |   +--|--+  |   +--|---+  |
        |   |  |  |   |  |  |   |   |  |  |  |   |  |   |  |
|       | | |       | |  |    |     |  ||        || |       |         |
f0      |   |      1000  |          |  2000      |  |      3000
        |   |         |  |          |  |         |  |
offset:425 595      1105 |        1785 |       2465 |
                        1445          1955         2635
chan:   1   2         3  4          5  6         7  8

Channel 1 is engineering channel in Baudot 50/340
          idles with mark tone active

Offset above shows MARK frequency: ch1: 425/765     ch5: 1785/2125
                                   ch2: 595/935     ch6: 1955/2295
                                   ch3: 1105/1445   ch7: 2465/2805 
                                   ch4: 1275/1615   ch8: 2635/2975

* POR-VFT      A 7 ch system has been found in use by the Portuguese Army. Each
               channel is shifted by about 200Hz and is based on ITA2 and runs 
               at 200bd per channel. Analysis suggests a synchronous baudot 
               with forward error correction. The system can be decoded using
               the Hoka Character Analysis Duplex module with settings on ITA2,
               5 bit and no-interleave. The system is used by the Portuguese 
               SFOR units based in Bosnia. Try 11198kHz or 11202.1kHz for a 
               sample. Listen for the LSB operator chatter between system 

  ** No channel layout yet **

|         |         |         |         |         |         |         |
f0                 1000                2000                3000

1-J. Phase Shift Keying systems

  Nearly all of the systems that we have outlined above use Frequency Shift 
  Keying (FSK) of one, two or more tones.  However, there are many signals to 
  be heard on HF which are Phase modulated (Phase Shift Keying or PSK) in 
  nature.  At present, only the Hoka Code30 is capable of demodulating such 
  signals, and as such, this area of "listening" remains a somewhat uncharted 
  area, and none of the systems known about so far have names like the ones we 
  use above!

  However, Hoka's Code 30 provides a tool-set that allows the user to determine
  the characteristics of a PSK system with little more effort than an FSK-based
  one. This at least allows us ordinary mortals to "fingerprint" certain types
  of system.  In a nutshell, here are the commonly encountered PSK-based 

      2-4MHz region:  Navigational aids sending Differential Global
      Positioning System (DGPS) information using 250bps 4-phase
      (or Quaternary) PSK (QPSK).  Try 2834.0, 2805.0, 3226.0kHz

      3-13MHz region:  Soviet Mil(MOD)/FAPSI/PTT system sending 1280bps data 
      using a 4-phase, Offset QPSK scheme. These stations are recognizable
      in that they are all placed on .081 offsets from a kilohertz or half 
      kilohertz point.  At least 20 channels are known to be in almost 
      constant use.  Try 9058.081, 7663.581, 5752.081, and 13369.081kHz
      amongst others. 
          Note: Recently many of these frequencies have been sprouting lower 
          sideband twins. For example 11422.081 is paired with 11417.93,
          9209.081 is paired with 9204.93. Presumably this means the system 
          is operational and adding more capacity.

      5-20MHz region: Unknown user and system sending 600bps data using 
      2-phase, or Binary PSK.  Try 10662.8kHz. 1200bps and 2400bps signals
      of a similiar nature have been found in this region also.

      2400-PSK         Believed to be a NATO and UK Royal Navy system, now 
                       occupying many channels and particularly active since
                       the deployment of IFOR in former Yugoslavia. Also many
                       75bd RATT channels used by the Royal Navy now have the
                       2400-PSK system present instead.  Sample of frequencies:
                       2535, 3370, 4578, 6410, 8158, 10480, 16164kHz

      1800-PSK         A number of signals have been noted sending 1800bps
                       QPSK data. User is unknown but suspect NATO and is
                       much rarer than the 2400-PSK.

      1600-PSK         Believed UK/US Mil system.  Sample of frequencies:
                       4757, 5237, 10386kHz.

      KRE-PSK          A North Korean BPSK system running at 1200bps. The
                       North Korean Diplomatic services are making use of this
                       system along with the usual Baudot.

1-K. Mystery systems

      This section lists signals that have conflicting information. Some may 
      be fabrications, some may be just unknown. These systems will be listed
      here rather then mix them among the confirmed and better documented 

new     108.8/170       An interesting FSK signal commonly logged in the UK
                        running at 108.8bd and a shift of 170Hz. Shows an ACF
                        of 32 during idle with a traffic ACF of 0. Very strong
                        AM carriers have been noted nearby with Counting Station
                        traffic after transmission indicating a US Intel source.

        1200-FSK        A 1200bps FSK system known to be used by the Italian 
                        Military or Diplo service.  Always has a distinctive 
                        .7kHz offset. Has been heard on 6811.7, 9126.7, 10485.7
                        and 13904.7kHz amongst other channels. Italian operator
                        chatter in USB on the carrier point can often be heard
                        prior to messages being sent.

        4+4             This is an 8 tone MFSK signal with a unique tone 
                        arrangement. It is a Chinese Diplo system with most
                        traffic originating from Peking. Its real name and 
                        base modulation mode (FSK/PSK) are unknown although
                        analysis suggests that each of the 8 channels is 150bd
                        or 75bd synchronous FSK. No estimation of total baud 
                        rate. The tones are grouped in sets of 4 spaced 300Hz 
                        apart with a 450Hz intergroup gap, 4 tones w/300Hz 
                        spacing, 450Hz gap, 4 tones w/300Hz spacing. Most 4+4 
                        signals seem to be centered on .74. For an example try 
                        the signal centered on 8321.74:

                             8320      8321      8321.74  8322
                               |    |    |    |    v   |    |    |    |
                               .61  .91  .21  .51      .96  .26  .56  .86

        AIRCALL         Another system with very little factual information.
                        This 7 tone MFSK system appears on the Klingenfuss 
                        recordings cassette on track 32. Sources indicate that
                        this system is also generally unknown so I will list it
                        here pending confirmation.

        ARTOR           Adaptive Robust Transmission Over Radio - an adaptive,
                        error-free mode for HF using QPSK. First mention of
                        this system found in the 13th Edition of the Code
                        Manual. Typical baud rates are documented to be 50,
                        100 or 200; automatically selected, ARQ and FEC modes
                        are supported. This system has never been logged and
                        probably has not been commercially released by the
                        developer, Ascom Radiocom Ltd, Switzerland. Ascom
                        did advertise the system (as "ARTOR, our new HF-modem")
                        in the June 1992 issue of Signal and probably exhibited
                        at CommunicAsia '92 in Singapore and AFCEA '92 in 
                        Washington D.C.

        QAM             A system reportedly used by the Chinese, unknown usual 
                        bd rates. A sample of this signal is available on the
                        Klingenfuss CD (CD#2/Trk9) or Cassette (Trk37). This is
                        also the name for the modulation technique Quad Phase
                        Shift Keying with Amplitude Modulation or Quadrature
                        Amplitude Modulation (QAM) commonly used in high speed
                        computer modems (9600-28800) and point-to-point micro-
                        wave communications. Not known to be on HF at this time.
                        No known loggings to date. Real?

        SUI-FEC         A new UNID FEC system running at 68.5bd, 85Hz shift
                        used by the Swiss Army. Traffic has an ACF=0 but an
                        ACF=10 at start of messages.

This table represents most of the unknown signals that have been contributed 
to the WUN logs column. This is the most speculative of all the information 
presented in this document. This table is constructed on the assumption that 
similiar baud rates and ACF indicate potentially similiar systems. Still, 
despite its speculation, it is a good indication of the number of unidentified
systems that are being used and a good pointer for further research. An 
unidentified system is defined as a system that could not be named by the
contributing monitors decoder. All loggings are based on at least 2 or more
loggings when possible. Any exceptions are noted in the comments area. The 
comment for an individual baud rate is a composite statement drawn from all 
loggings for a specific rate.

If a star appears to the right of the baud rate in the chart below it means
there is a separate paragraph broken out which goes into more detail then the
simple chart provides. 

The following systems have been identified

800bd IRA-ARQ
363.78|  375| 25           |   | 'CWB' Bulgarian Embassy, London

IRA-ARQ idling
300.01|  500| 55           |   | bit stream

600bd IRA-ARQ
272.73|  450|              |2.c| Possible Russian TDM system

   +-------------------------------------- Baud (or bps, when labelled)
   |      +------------------------------- Shift (Hz)
   |      |      +------------------------ ACF or signal period
   |      |      |           +------------ First identified/WUN issue
   |      |      |           |    +------- Comments [in () is FAQ name]
   v      v      v           v    v                 
398.27|  703|              |2.a|
362.4 |  500| 10           |2.7|
360.5 |  780|              |2.9| acks @301/780 packet-like
301.5 |     | hdr:8        |1.a| Packet-like, w/orig. MFA Helsinki?
300.6 |  190|              |2.9| 10bit/char 1200bits/burst DGPS like.
300.12|  850| 448          |2.9|
300   |  800| 0            |pst| 57bit preamble
300   |  200| 10           |   | various orgs sending DGPS info in MSK
300   |  200| 17           |2.a| 3s bursts, packet-like
250   |  170| 22           |3.3|
250   |  150| 75/150       |3.2| fast ARQ system
250   |  170| 15/75        |2.6| ARQ w/ITA2 orig. Western Africa
      |     |              |   | probably not DUP-ARQ-2
250   |  850| 32/176       |2.7| Possible ARTRAC-II/DUP-ARQ-2 signal
250   |  170| 19/38/57/76  |2.5| FSK data bursts, w/orig. Korean Diplo?
225   *  170| hdr:8        |2.8| Packet-like (new R&S-ALIS mode?)
216.07|  114| 84           |2.b|
203.56|  400|              |3.1| 4sec idle sequence
200.3 |   85|              |2.3| Logged in the 250-350kHz range
200   |  170| 250          |pst| ARQ,simplex, 250bit frame, polarity switch
      |     |              |   | each frame (pos/neg)
200   |     | 64           |2.6| sounds like VFT, 6-peaks
200   |  400|              |2.7| sounds like ARQ6-90/98
200   |  450|              |   | sounds like ARQ-E/E3
200   | 1000| 0            |2.9| FSK
200   | 1044| 646          |3.3| Probable Russian Air Force system
186.6 |     |              |   | FEC bit-stream, very rare
178   |  240|              |pst| similiar to 80.5 but w/16bit frame
161   |  330|              |2.9| unusual 12bit frame RTTY w/ITA2 bit interleave
      |     |              |   | Most likely East European (POL) source. 
      |     |              |   | see 121/330
150   |  100| 28/224       |2.6| FEC, also as 75/100 from MOSSAD, Tel Aviv
150   | 1700|              |2.7| unusually wide shift
150   *  170|              |   | VFT w/3ch 150/170 (3 ch 150 FSK)
150   |  853| 1399         |3.3| big ACF value!
144   *  200|              |   | VFT w/3ch 144/200 (RUS-144)
144   |  170| 0            |2.7|
126   |  250| 7            |2.a|
120.96|  330|              |2.9| unusual 12bit frame RTTY w/ITA2 bit interleave
      |     |              |   | Most likely East European (POL) source. 
      |     |              |   | see 161/330.
115.74|  380|              |   | 23-bit frame
110   |  170| 0            |   | scrambled ASCII? common in the US, maybe NATO
109.81|  170| hdr:64 tfc:0 |   |
109.3 |  340|              |2.1| Decoded by Sitor-b. Logs from the US
108.9 *  170|0/32/64/96/200|2.4| Logs from UK, FEC/8bit char, most likely US
      |     |idl:32 tfc:0  |   | Intel source or US Mil/Air Force
107.53|  500|              |   | Most likely an encrypted CIS system
100.3 |~ 200| 38/76        |2.3| VFT w/2ch 100.3/(150-200) 1kHz ch shift ALE?
      |     |              |   | (Spanish Navy)
100   |3*400| 190          |2.7| -600/-200/+200/+600; 4-tone clover?
100bps*6*200|              |2.7| 7ch ea tone 100/200bps 4DPSK modulated
      |     |              |   |  (POR-VFT)
100   |  500| 162          |3.b| possible 12char per burst
 80.5 |~ 300|              |pst| also 81.5,122.2,161.0,163.0, 12bit frame 
 75   |  850| hdr:65 tfc:0 |2.8| hdr: 64 or 65  NATO System?
 75   |  250|              |   | VMGTCNREX crypto sequence recorded with ITA2
      |     |              |   |  6-bit/interleaved. Maybe CIS-MIL
 75   |  200| 300          |3.b| Russian or UKR
 75   |  170|              |2.8| 10bit async, not ASCII, not ITA2
 75   |   70| 0            |2.8| VFT w/2ch 75/70 FSK from GYA/RN,UK
 70.1 |     |              |   | unid FSK signal
 68.5 *   85| hdr:10 tfc:0 |   | Not AUTOSPEC (SUI-FEC)
 46.1 |  240|              |3.3| Idle on reversals
 54.13|  500|              |2.b| CIS Synchronous data stream
 50   |  500| 136          |   | parallel found on other freqs. Shifts 250&500
 50   |  250| 136 or 272   |2.9| Russian?
 46.1 |  240|              |3.3| Idle on reversals
 ??   |48*??|              |2.6| 49-tone modem w/620Hz pilot on 15919.0
 ??   |var. |              |2.8| 7 chars of ITA2-P beta+7 zeros: ARQ-E like

o WUN issues are numbered 1-9abc for short, where 'c' is 12 or the Dec issue.
o "pst" - posted to the group list

Section 2. Modes on VHF.

  There are data signals on VHF, currently dominated by pager systems.  This 
  area will continue to grow over time as more capability is added to existing
  systems. They are included here for reference purposes. Many of the high end
  professional analysis units include a few of the pager modes. But keep this
  in mind - according to the ECPA, monitoring of all types of paging signals is
  illegal and the transmissions are considered private. The ECPA, of course,
  only applies to the US and there may be different laws covering paging signals
  in effect in other countries.

  But...not all modes found on VHF are dedicated to paging, there are also
  systems used by the Aviation industry, Public Data Networks, the amateur 
  radio community and some European Security forces/Police.

2-A. VHF Data Signals

        ACARS           Aircraft Communication and Reporting System. A packet-
                        like 2400 bps MSK digital air to ground system for
                        passing plane data and messages. 

                        Check the following frequencies in AM mode for signals. 
                            131.550 (US primary) 
                            130.025 (US secondary)
                            129.125 (US tertiary)
                            131.475 (Air Canada proprietary channel)
                            131.725 (Europe primary)
                            131.525 (Europe secondary)
                            131.825 (Europe)
                            131.450 (Japan primary)

        GMDSS/DSC       DSC on VHF is the same as DSC on MF/HF except that the
                        system uses a 1200 bd and the packet is very short,
                        only about 0.5 sec. Frequency used is Ch. 70 - 

        EMWIN           Emergency Managers Weather Information Network is an 
                        experimental data service, formerly known as WWIN 
                        (Wireless Weather Information Network), run by the 
                        National Weather Service that utilizes a 1200 baud 
                        ASCII Bell 202 signal to transmit a hypertext system 
                        (maps and text together) that lists weather conditions.
                        It is possible to reprogram some of the professional 
                        units (such as the M7000) to receive the text infor-
                        mation, but special software is required to fully use
                        both maps and the text. Areas currently supported:

                         Location              Watts         Frequency MHz
                         -----------------     --------      ----------------
                         Washington, DC        600watts      163.35
                         Norman, OK             50watts      169.025
                         Tulsa, OK             250watts      165.0125
                         Oklahoma City, OK     300watts      150.525
                         Wichita Falls, TX     ---           KTEO/90.5 FM
                                                             92kHz subcarrier

                        Note: the data is also transmitted from GOES 8, GOES
                              9, G4/Ku tr 4 and T1/Ku tr 5a.

        FMS-BOS         Funkmeldesystem fur Behorden und Organisationen mit 
                        Sicherheitsaufgaben loosely translated as Radio 
                        Calling/Communications System for Authorities and 
                        Organizations with Security Concerns. Supports a baud 
                        rate of 1200 and uses BCD for all digits. This system
                        is designed to minimize overall traffic by transmitting
                        a series of codes in 48bits. The 48bits are divided 
                        into 6 parameters: BOS-id, Country-code, Trunk-code,
                        vehicle-id, status, special-use.

        INFOCALL        A German pager-like system used to deliver stock
                        data and news services. Supports a baud rate of 1200bps
                        using the ITA-5 character set.

        ATIS            A VHF/UHF radio signal used on the River Rhine maritime
                        radio. This identification signal is automatically 
                        generated at the end of speech transmission in 1200
                        baud FSK (mk/sp frequencies of 1300/2100Hz). The data 
                        consists of a country identifier and a call sign. This
                        system is used in Germany, Luxombourg, France, Switzer-
                        land, Holland and Belgium.

                        ATIS is also the name of an aircraft communications
                        system running at 2400bps w/ITA5.

        MPT1327/1343    A 1200bps trunking protocol first defined in 1987 by 
                        the UK Department of Trade and Industry. The system 
                        operates in VHF 136MHz to 178MHz and UHF 403MHz to 
                        528MHz. MPT1343 is the standard that defines the 
                        behavior of radio units on the public network. The 
                        protocol supports a variety of features such as con-
                        ference calling, call transfer, calling of PABX and 
                        PSTN numbers, wide area roaming, traffic jam pre-
                        vention, interference prevention and automatic user 
                        location and registration. These protocols are 
                        currently handled by the Wavecom W4100dsp, W41pc and
                        Hoka Code 30.

2-B. Special Amateur Digital/Video Modes

        These modes can be found in the 6 meter (50 mhz), 2 meter (144-148 
        mhz), 220 mhz, 430-450 mhz ranges (70 cm.) and higher ranges. They are
        primarily used by Amateurs, and some of them require special hardware 
        or software to view or use. These are capsule descriptions only; there
        are several good books and magazine articles published in 'QST', '73' 
        and 'CQ' magazine which go into much more detail on these modes. Please
        consult them for more information.

        DSC             'Digital Selective Calling'. This is a system utilized
                        in the amateur service that allows suitably equipped 
                        radios (such as those sold by Yaesu and Icom) to send 
                        an ASCII burst signal that allows hams to page each
                        other by callsign over a repeater. It is somewhat 
                        similar to POCSAG.
        PACKET          This mode is very similar to that found on HF, except 
                        that a different tone set (typically Bell 202 tones) 
                        are utilized. These signals can be found in almost all 
                        the ham bands, including 900 mhz. There are 3 distinct 
                        protocols in use here;

            AX.25       Similar to that on HF, but speeds here are typically 
                        1200 bd FSK or 9600 bd FSK or PSK in the UHF/SHF
                        range. Some applications using AX.25 are:

                        * Packet Cluster - This is a real-time networked mode
                          that allows connected amateurs to immediatly report
                          on DX stations and broadcast this information to 
                          whomever may be connected. One of the most common 
                          frequencies is 145.55MHz.
                        * APRS - somewhat similar to HF with different baud
                          speeds being used here. The national frequency for
                          this mode on 2 meters is 145.57MHz.
                        * TCP/IP - Transmission Control Protocol, Internet 
                          Protocol. This mode, which uses AX.25 as the Link
                          Layer, is used, for example, in links between 
                          Internet and amateur BBSs. Due to the nature of the
                          protocol and speeds used (9600 bd or better), units 
                          like the M8000 will not read this data. However, 
                          units with special software and firmware (such as 
                          that found on the PK232) can utilize this mode. Units
                          operating in this mode are said to be in 'KISS' mode.
                          This traffic may be found on 2 meters on 145.59MHz 
                          (and others).

        ATV             Amateur Television.  This is a FSTV system used by hams
                        in the 430, 900 and 1200 Mhz systems.  Uses include 
                        public service and Space Shuttle relays. A special de-
                        modulator is required to see this system in most in-
                        stances; however, some cable TVs can also see this 
                        system on channels 60, 62 or XX.

2-C. VHF SELCAL and Analog Paging Signals.

        There are a lot of commercial systems available that are being used 
        today. Till I get a handle on all the different manufacturers and get
        the information collated check out the following page. It covers and
        presents the tones used by many commercial systems.

        HSC             Hexadecimal Sequential Code format is an analog system
                        introduced in 1979 that supports tone-only, numeric and
                        voice paging. It is based on the 5/6-tone system but
                        uses a total of 16 tones (0-9 A-F + Repeat). Selected
                        combinations of tones can be used to activate special
                        features built into the pager. HSC and 5/6-tone systems
                        can work together on the same frequency.

        European 5/6-tone Systems
        This analog paging format uses tone sets defined by various European and
        United States standards organizations. This analog system uses 10 tones
        plus one extra tone (in most cases) as a Repeat tone. The Repeat tone
        is used when two tones representing the same number follow in sequence.
        For example: 99222 would use the tone sequence 9R2R2. Pagers using this
        format support up to 1 million pagers and support tone-only and voice
        Tones supported are listed in the following as digit/frequency in Hz.
        Also see Table 4-H.

        CCIR1, CCIR2, CCITT, EIA, NATEL, ZVEI1/2, VDEW and EURO5 are 5 tone.
        EURO is 6 tone.

    +   EEA    - SELCAL system conforming to Electronic Engineering Association, 
                 United Kingdom. recommendations. Tones supported 0/1981 1/1124
                 2/1197 3/1275 4/1358 5/1446 6/1540 7/1640 8/1747 9/1860 A/1055
                 B/930 C/2246.9 D/991 E/2110 F/0 with a tone duration of 40ms.
    +   CCIR 1 - CCIR 1 recommendations from Comite Consultatif International 
                 De Radio. Tones supported 0/1981 1/1124 2/1197 3/1275 4/1358
                 5/1446 6/1540 7/1640 8/1747 9/1860 A/2400 B/930 C/2246.9
                 D/991 E/2110 F/0 with a tone duration of 100ms.
    +   CCIR 7 - SELCAL system conforming to CCIR 7 recommendations from
                 Comite Consultatif International De Radio. Tones supported
                 0/1981 1/1124 2/1197 3/1275 4/1358 5/1446 6/1540 7/1640 
                 8/1747 9/1860 A/2400 B/930 C/2246.9 D/991 E/2110 F/0 with
                 a tone duration of 70ms.
    +   ZVEI 1 - SELCAL system conforming to ZVEI 1 recommendations from
                 Zentralverband der Electrotechnischen Industrie, West Germany.
                 Tones supported 0/2400 1/1060 2/1160 3/1270 4/1400 5/1530
                 6/1670 7/1830 8/2000 9/2200 A/2799.9 B/810 C/970 D/886
                 E/2599.9 F/0 with a tone duration of 70ms.
    +   ZVEI 2 - SELCAL system conforming to ZVEI 2 recommendations from
                 Zentralverband der Electrotechnischen Industrie, West Germany.
                 Tones supported 1/2200 2/970 3/1060 4/1270 5/1400 6/1530 
                 7/1670 8/1830 9/2000 A/2599.9 B/2799.9 C/810 D/886 E/2400 F/0
                 with a tone duration of 70ms. Also called DZVEI.
    +   NATEL  - SELCAL system conforming to Scandinavian National Telephone
                 (NATEL) recommendations. Tones supported 0/1633 1/631 2/697
                 3/770 4/852 5/941 6/1040 7/1209 8/1336 9/1477 A/1633 B/600
                 C/1995 D/2205 E/1805 F/0 with a tone duration of 70ms.
    +   EURO   - SELCAL system conforming to EURO recommendations. Tones
                 supported 0/979.8 1/903.1 2/832.5 3/767.4 4/707.4 5/652.0
                 6/601.0 7/554.0 8/510.7 9/470.8 A/433.9 B/400.0 C/368.7 
                 D/1153.1 E/1062.9 F/0 with a tone duration of 100ms. Also
                 referred to as EuroSignal. This system uses 6 tones.
    +   EURO5  - SELCAL system as above but uses 5 tones.

    Motorola Systems
    +   EIA   - SELCAL system conforming to Electronics Industries Association,
                United States (EIA) recommendations. Tones supported 0/600 
                1/741 2/882 3/1023 4/1164 5/1305 6/1446 7/1587 8/1728 9/1869
                A/2151 B/2432.9 C/2010.1 D/2292 E/459 F/0 with a tone duration
                of 33ms.
        MODAT - Tones supported 0/637.5 1/787.5 2/937.5 3/1087.5 4/1237.5
                5/1387.5 6/1537.5 7/1687.5 8/1837.5 9/1987.5

    REACH 11th root of 2
        High Freq - 0/2400 1/2253 2/2116 3/1987 4/1865 5/1751 6/1644 7/1544
                    8/1450 9/1361
        Low Freq  - 0/1200 1/1127 2/1058 3/993 4/933 5/876 6/822 7/772 
                    8/725 9/681

    +   CCITT   SELCAL system conforming to CCITT recommendations. Tones
                supported 0/400 1/697 2/770 3/852 4/941 5/1209 6/1335 7/1477
                8/1633 9/1800 A/1900 B/2000 C/2100 D/2200 E/2300 F/0 with a
                tone duration of 100ms. 
    +   VDEW    SELCAL system conforming to VDEW recommendations or German
                Electricity Works - Vereinigung Deutscher Elektrizitaetswerke.
                Tones supported 0/2280 1/370 2/450 3/550 4/675 5/825 6/1010 
                7/1240 8/1520 9/1860 A/2000 B/2100 C/2200 D/2300 E/2400 F/0
                with a tone duration of 100ms.
    + Hoka Code 30 can decode but needs the VHF option (extra) to decode
      these modes.

2-D. VHF Digital Paging Signals. 

         POCSAG         Post Office Code Standardization Advisory Group Pager
                        system developed in 1981 and is described in CCIR
                        Recommendation 584, Radiopaging Code 1. This system 
                        can handle up to 2 million individual addresses per 
                        carrier and can support tone only, numeric and text 
                        pagers. Operates at 512, 1200 and 2400 bps (1200 and 
                        2400 bps are commonly referred to as Super-POCSAG. 
                        Transmits in FM Narrow using frequency bands that are 
                        country specific. POCSAG is an asynchronous protocol, 
                        it has a start up preamble signal that alerts the pager
                        to an incoming message (wake up). Pagers are assigned
                        to 1 of 8 groups based on address. Pagers only pay
                        attention to the address group to which they are
                        assigned. 2 coding formats are used for message text:
                        BCD and 7 bit ASCII. Some documents reference POCSAG
                        by the short-tag PAGER1.

         ERMES          European Radio Message System developed in 1990 by the
                        European Telecommunications Standards Institute. 
                        Strictly a European format with no known US implemen-
                        tations. It supports alphanumeric, numeric and tone 
                        paging. ERMES operates at a constant speed of 6250 bps
                        and uses 4 level FSK signalling. This protocol uses a 
                        dedicated frequency spectrum in the 169 MHz range and 
                        supports 16 adjacent channels. The pagers are designed 
                        such that each pager is assigned to a specific time 
                        slot and when the pager senses it is not in its 'home'
                        system it begins its roaming routine by scanning all

         GOLAY          Golay Sequential Pager Signalling System is a digital
                        system used to transmit tone only, numeric, alphanumeric
                        and voice pages. This is a Motorola proprietary system
                        but now obsolete according to Motorola. It may be that
                        GOLAY is no longer found in those VHF frequency bands
                        that support pagers but is still believed to be on US 

                        Pagers are divided into groups and a preamble is sent
                        prior to paging alerts. Only pagers within the group
                        number sent in the preamble need to examine the data
                        stream for their address. Supports bit rates of 300 or
                        600 in that a pager address is sent at 300bps and any 
                        numeric or alphanumeric information is sent at 600bps.
                        Also known as GSC - Golay Sequential Coding.

         APOC           Advanced Pager Operating Code. A new mode, developed
                        by Philips Telecom and announced in 1993, that offers 
                        higher speed and some new features while retaining 
                        backwards compatibility with POCSAG. Supports bit 
                        rates between 1200 to 6400 or about 1200 to 3200 baud
                        using 2-PAM/FM or 4-PAM/FM modulation. Extended
                        addressing is supported, allowing support for more then
                        2 million pagers. As of mid-1996, Philips has dropped
                        APOC and instead settled a cross-licensing deal with
                        Motorola for access to FLEX.

         FLEX           Paging protocol introduced by Motorola late in 1994 and
                        will be the protocol of choice as paging company up-
                        grade from POCSAG to FLEX in the US. FLEX supports rates
                        of 1600, 3200 and 6400bps and can handle up to 5 billion
                        addresses. FLEX has a 4 frequency signal arranged as 
                        evenly spaced tones with usual shifts (in Hz) of: 
                        This signalling technique is also more susceptible to 
                        noise so a robust error correction scheme is incorp-
                        orated. FLEX pagers also appear to have a decreased 
                        effective paging radius when compared to POCSAG.

                        FLEX is a synchronous time slot protocol. The FLEX
                        protocol does not send messages at random but instead
                        sends all paging data destined for a particular pager
                        during a pre-defined time slot. The pager only wakes
                        up only when a message is expected to arrive in real
                        time thereby saving battery life.

        NEC/D3          A digital encoding format developed by NEC America that
                        supports tone only and numeric pages at a rate of 200
                        bps. This format was developed for use in NEC R3-D3
                        pagers. This format uses 2 methods for preserving
                        battery life. First a preamble is used to alert ALL 
                        pagers that there are incoming messages. Pagers remain 
                        idle till preamble detection. Second, pagers are 
                        grouped by address into 1 of 4 different groups. Each
                        group is transmitted during a fixed time period and
                        pagers only power up to look for its own address during
                        the time its group is transmitted. Error correcting
                        codes and even parity bits are used on each address and

         Mark IV/V/VI   A digital format that supports tone, numeric and voice
                        paging. This system requires 2ms to send a binary 0 and
                        4ms to send a binary 1 making the data transmission 
                        rate between 250 to 500 bps. Mark IV could handle
                        tone only and Mark V and Mark VI could handle up to 10

         Swedish MBS    An FM subcarier system developed by the Swedish
                        Telecommunications Administration. This paging format
                        supports tone-only, numeric and alphanumeric paging.
                        Data is transmitted using the 57kHz subcarrier at a 
                        rate of 1187.5 bps. MBS (Mobile Search) is used in a 
                        modified form (MMBS) in the US by Cue Paging. 

         RBDS/RDS       An FM subcarrier system developed by the Swedish
                        Telecommunications Administration. The system transmits
                        information to standard FM receivers using the 57kHz 
                        subcarrier with a data rate of 1187.5 bps. The signal
                        is made up of 16 possible data groups, where each
                        has 4 blocks of info and each block is 26 bits long.
                        Out of the 26 bits, 16 bits are for data and 10 bits
                        are for error correction. RBDS data groups currently
                        supported are:

                        0 Basic Tuning/Switching    8 Traffic Msg Channel/TMC
                        1 Program Item Number       9 Emergency Warning System
                        2 Radio Text               10 PTY Names
                        3 GPS                      11 Undefined
                        4 Clock Time & Date        12 Undefined
                        5 Transparent Data Chan    13 Undefined
                        6 In House Applications    14 Enhanced Other Networks
                        7 Radio Paging Services    15 Fast Tuning/Switching Info

                        Reference the NRSC US RBDS Standard 1/8/93: Specifi-
                        cation of the Radio Broadcast Data System and the
                        European Standard CENELEC EN 50 067 (4/92): Specifi-
                        cation of the Radio Data System.

                        Circuit Research Labs SC-100 is an example of an RBDS
                        processor used to inject the proper carrier in an FM

         RECEPTOR       An FM subcarrier system developed by Seiko Tele-
                        communications Systems, Inc. The systems uses the 64kHz
                        subcarrier on commercial FM broadcasts and operates 
                        with a data rate of 19kbps. The system offers a variety
                        of services including paging, sports, weather reports,
                        and stock quotes through the Seiko MessageWatch. The 
                        system is currently in limited use in the US with 
                        expansion planned into the top 20 US markets within 
                        the next 2 years.

2-E. VHF Two-way Paging Signals

        ReFLEX          A Motorola two-way paging scheme. Currently comes in 2
                        forms. ReFLEX 25, which supports an outbound channel 
                        capacity of 12,800bps and inbound capacity up to 9600
                        bps and ReFLEX 50, which supports an outbound channel
                        capacity of 25,600bs and inbound capacity up to 9600
                        bps. Both forms utilize a 50kHz channel. This scheme 
                        is designed to give the end user the ability to ack-
                        nowledge a message, send replies and download data.

        inFLEXon        A Motorola two-way paging protocol that allows voice
                        and data messaging using a 50kHz Narrow Band PCS
                        channel with a throughput of 112K bps. This system
                        is based on the ReFLEX protocol.

        NexNet          A proprietary two-way system created by Nexus Tele-
                        communications, Ltd. of Israel uses Spread Spectrum
                        transmission from the pager to send responses. The 
                        current system uses POCSAG to send messages to the 
                        pager. Data sent outbound from the pager is transparent
                        to the incoming data which means that this two-way 
                        paging system can coexist on pre-existing one-way paging
                        channels. Testing in Minneapolis, Chicago and Orlando
                        by American Paging is expected to be completed by the
                        end of 1996.

        RAMP            Radio Mail Protocol. A two-way pager protocol built 
                        to be backwardly compatible with APOC.  Currently 
                        under development by Philips Telecom.

        pACT            An AT&T Wireless Services/PCSI developed open standard
                        designed to support two-way paging and messaging 
                        services. The protocol uses an 8kbps link based on
                        re-use of cellular channels.

    * POCSAG and GOLAY can also be found on U.S. domestic C/Ku-band Satellite 
      SCPC carriers.

Section 3. Baud Rate Summary Table

Below is a table of expected baud rates you can most likely encounter for 
the latest listing of modes available. An accurate baud rate is a valuable 
tool to identifying a particular mode and there are many modes that have 
unique baud rates. As of this writing the Hoka and Wavecom units seem to 
have the most accurate capability of all existing decoders currently on
the market. 

All rates are in units baud.

A few baud oddities of note: 

  * 128.5bd ARQ-M2 French Forces circuit(s) between Papeete, Tahiti and Mururoa.
  * 184.6bd ARQ-E French Forces circuit(s) used by RFFXQA Sarajevo, BIH also
    it seems many former 72bd ARQ-E circuits are changing to 184.6bd ARQ-E.
  * 384bd FEC-A used by MFA Paris,F and French Emb., ROU
  * 109.3bd SITOR-B used by an unidentified user.
  * 46.1bd ARQ-E used by Egyptian/Tunisian Air Force/Air Defense sending 
    in Arabic.
  * 85.7bd ARQ-E used by an unidentified user sending encrypted traffic

For baud rates of unidentified systems reference the table in section 1-K

Synchronous Data Block Systems

96		SI-ARQ
125		DUP-ARQ
144		SI-ARQ
171.42		IRA-ARQ
192		SI-ARQ
200.20		IRA-ARQ
250             DUP-ARQ-2
300.30		IRA-ARQ

Packet-like Systems

225             MERLIN/ALIS
240             HC-ARQ
1200            ACARS/HFDL

Multi-tone/MFSK Systems

12.5            COQUELET-13
13.33           COQUELET-8
20              COQUELET-13 PICCOLO-Mk6
26.67           COQUELET-8
40              COQUELET-13 CROWD36 PICCOLO-Mk10
100             MIL188 TT2300b
240             MERLIN/ALIS-2(7 tone burst ARQ ALIS mode)

1364 b/s        LINK-11
2250 b/s        LINK-11

Synchronous Bit Stream Systems

36              BEE/36-50
36.5		81-81
40.5		81-81
42.1		CIS-14
46.1            ARQ-E
47.5		CIS-14
48 		ARQ-E ARQ-E3 ARQ-N CIS-14
50		CIS-11 CIS-14 ARQ-E BEE/36-50
62.3		AUTOSPEC SPREAD-11/21/51
70.5		CIS-14
73		81-81
81		81-81
83.3		CIS-14
84.21		CIS-14
85.7		ARQ-E ARQ-M2-242/342 ARQ-N
86		ARQ-E ARQ-E3
87		ARQ-M2 ARQ-M4
94.11		CIS-14
                ARS-GUARD SI-FEC
100.05		HNG-FEC
102.7		AUTOSPEC SPREAD-11/21/51
109.3           SITOR-B
110		IRA-ARQ
125             ARS-GUARD DUP-FEC-2
128.5           ARQ-M2-342
137		SPREAD-11/21/51
162             81-81
164.48		ROU-FEC
171             ARQ-E
171.42          IRA-ARQ
172		ARQ-M4-242/342
184.6		ARQ-E
                ARS-GUARD HNG-FEC
218.3		ROU-FEC SPREAD-11/21/51
240		IRA-ARQ
267             RAC-ARQ
288		FEC-A CIS-14 ARQ-E
300		IRA-ARQ CIS-11
384             FEC-A
600		IRA-ARQ

Asynchronous Bit Stream Systems

110		ASCII
300		ASCII

Section 4. ACF Summary Table

Definition: ACF - AutoCorrelation Frequency, a number that is derived from
            the Auto Correlation BIT module in the Hoka Code 3 or Code 30.
            The technique and theory of Autocorrelation is not limited to
            Hoka equipment as Wavecoms W41PC and W4100DSP also include this
            analysis tool.

Result:     ACF can tell you: 

                1. Character size -or-        Needed if you wish to apply an
                   Frame size                 alphabet against an unknown
                                              signal w/Simplex or Duplex
                   Character Repetition       Analysis modules.
                   Cycle (CRC)

                2. Signal is encrypted        ACF=0 or no pattern

Theory:     Autocorrelation is simply the correlation of a signal with itself 
            or a comparison of a signal with itself as a function of time 
            shift. By determining the first highest peak in the graphical
            display of the Auto Correlation BIT module it is possible to 
            discover the periodicity of a signal. This allow you to determine
            the number of bits in a character of a particular signal or the 
            frame size of a signal. It also will reveal the randomness of a 
            signal which instantly tells you if a signal is encrypted. Ideally,
            encrypted signals contain no regular patterns.

Below is a table of known signals and their ACF values. In the table, 
"Preamble" is defined as the non-random portion preceeding an encrypted signal.
Many believe that this is used to sync the transmitter and receiver of the
signal being transmitted. For signals that are mostly off-line encrypted
(figure/letter group encryption) or sent clear text "data" is defined as the
time which the signal is actually transmitting data or not idling. Many signals
don't have a distinct idle sequence but instead transmit data then terminate.
"Idle" is defined as the time the signal is sending an idle sequence. Many 
signals have distinct idle modes and spend many hours idling. Many times you
will see a different pattern displayed by the auto correlation BIT module of
a signal sending data and idling but they will have the same ACF.

        +------------------------------------- System name
        |             +----------------------- Preamble ACF
        |             |        +-------------- Data/Traffic ACF
        |             |        |         +---- Idle ACF
        v             v        v         v     Comment
BEE/36-50        |   70   |    0    |    2    | tfc is encrypted
81-81            |        |    0    |         | tfc is encrypted
ARQ6-70          |        |         |   70    | rare
ARQ6-90          |        |         |   90    |
ARQ6-98          |        |         |   98    |
ARQ-E            |        |  28,56  |   28,56 | very common, mostly idle
ARQ-E3           |        |  28,56  |   28,56 | very common, mostly idle
ARQ-M2           |        |  56     |   56    | French Forces 4-CRC
ARQ-M2           |        |  112    |   112   |               8-CRC not common
ARQ-M4           |        |  56     |   56    | rare
ARQ-N            |        |         |         |
ARS-GUARD        |        |         |   48,96 |
ASCII            |        |  7,8    |         | async system
AUTOSPEC         |        |  40(*)  |         |
BAUDOT           |        |  7,8,15 |         | 1 async system5 w/half-stop bit
CIS-11/TORG-11   |        |         |         |
CIS-14           |        |         |         |
DGPS (MSK)       |        |  10     |         |
DUP-ARQ          |        |  88     |         |
DUP-ARQ-2        |        |         |         |
DUP-FEC          |        |         |         |
FEC-A            |        |         |   56    |
FEC-S/SI-FEC     |        |         |         |
G-TOR            |        |         |         |
HNG-FEC          |        |   90    |   90    |
IRA-ARQ          |        |   11    |   55    | 
PACTOR           |        |    0    |         |
POL-ARQ          |        |         |    7    |
ROU-FEC          |        |   16    |   16    |
RS-ARQ/ALIS      |        |  110(*) |   59    | 228.7bd
RS-ARQ/ALIS2     |        |         |   59    | 240bd multitone signal
RS-ARQ/packet    |        |    0    |         | 225.2bd, tfc 0 due to encoding
SI-ARQ/ARQ-S     |        |         |   70    |
SITOR-A          |        |         |   45    | very common
SITOR-B          |        |         |   35    | very common
SPREAD           |        |         |         |
SUI-FEC          |   10   |    0    |         |
SWED-ARQ         |        |         |   45    |
TT2300b          |        |         |    8    |
TWINPLEX         |        |         |         |

(*) data from snapshots in the Klingenfuss Radioteletype Code Manual 13th Ed.


The data listed below is ACF sorted numerically. ACF in [] is an unknown
system that had a distinctive ACF. This data was taken from the Unid
Signals listed in section 1-K.

 ACF   System
----   -----------------------------------------
   2   BEE/36-50(idle)
   7   BAUDOT(x-stop), POL-ARQ
[  7]  126/250
   8   BAUDOT(x-stop) ,TT2300b
  10   RS-ARQ(225.2b), DGPS(MSK), IRA-ARQ
[ 10]  362.4/500
  11   IRA-ARQ
  15   BAUDOT(1.5-stop)
[ 15]  250/170 (West. African ARQ)
  16   ROU-FEC
[ 17]  300/200
  28   ARQ-E, ARQ-E3
[ 28]  150/100 (MOSSAD FEC system)
[ 32]  ARTRAC-II
  35   SITOR-B
  48   ARS-GUARD(idle)
  55   IRA-ARQ
  56   ARQ-E, ARQ-E3, FEC-A, ARQ-M2, ARQ-M4
  59   RS-ARQ/ALIS2(240b), RS-ARQ/ALIS(228.7)
  70   ARQ-S
[ 75]  250/170 (West. African ARQ)
[ 84]  216.07/114
  88   DUP-ARQ
  90   ARQ6-90
  96   ARQ-GUARD
  98   ARQ6-98
 110   RS-ARQ/ALIS
 112   ARQ-M2
[162]  100/500
[176]  ARTRAC-II
[224]  150/1000 (MOSSAD FEC system)
[448]  300.12/850
[1399] 150/853

Section 5. System Parameters

This section lists the unique characteristics of each named mode: specifying
character length and known alphabet for all modes. For synchronous data block
systems, block length, cycle specifics and baud rate is listed. For sychronous
bit stream systems, cycle information and character specifics, such as sync
bits, parity bits and interleaving details are listed. Finally for the MFSK
systems, tones, tone layout and tone spacing are listed. 

                 Synchronous Data Block Systems - Table 5-A

           +------------------------------------------ character size (bits)
           |     +------------------------------------ alphabet in use
           |     |       +---------------------------- block size (chars)
           |     |       |   +------------------------ repetition cycle (bits)
           |     |       |   |     +------------------ total rep. cycle time(mS)
           |     |       |   |     |       +---------- cycle breakdown as
           |     |       |   |     |       |           (ISS/IRS/rest)
           |     |       |   |     |       |        +- most commonly found baud
           v     v       v   v     v       v        v  comments
ARQ6-70   | 7 |ITA3   |  6| 70 |  350 | 42/7/21  | 200 |6ch*35ms=210ms 140ms ps
          |   |       |   |    |      |          |     |rare
ARQ6-90   | 7 |CCIR476|  6| 90 |  450 | 42/7/41  | 200 |6ch*35ms=210ms 240ms ps
ARQ6-98   | 7 |CCIR476|  6| 98 |  490 | 42/7/49  | 200 |6ch*35ms=210ms 280ms ps
SWED-ARQ/ | 7 |CCIR476|  3| 45 |  450 | 21/7/17  | 100 |3ch*7bit=210ms 210ms ps
ARQ-SWED  |   |       |  9| 90 |  900 | 63/7/20  | 100 |9ch*7bit=630ms 270ms ps
          |   |       | 22|180 | 1540 |154/7/19  | 100 |22ch*7bit=1540ms 260ms
TWINPLEX  | 7 |CCIR476|2*3| 45 |  450 | 21/7/17  | 100 | See Table 4-F
SITOR-A   | 7 |CCIR476|  3| 45 |  450 | 21/7/17  | 100 |3ch*70ms=210ms 240ms ps
SI-ARQ/   | 7 |ITA3   |  3| 42 | 437.5| 21/7/14  |  96 |every odd cycle has
ARQ-S/    |   |       |  4| 56 | 583.3| 28/7/21  |  96 |all bits inverted
ARQ1000S  |   |       |  5| 70 | 729.2| 35/7/28  |  96 |RC of 5 and 6 are
          |   |       |  6| 84 | 875.0| 42/7/35  |  96 |most commonly found
          |   |       |  7| 98 |1020.8| 49/7/42  |  96 |
DUP-ARQ/  | 5 |ITA2+7p|  5| 88 | 704  | 32/32/12 | 125 |7p added to ea. blk of
ARTRAC    |   |       |   |    |      |          |     |5 char. each xm burst
          |   |       |   |    |      |          |     |is 32bits. 5ch @ 5bits
          |   |       |   |    |      |          |     |+ 7p=256ms xm 96ms ps
DUP-ARQ-2/| 5 |ITA5 or|   |176 | 704  |          | 250 |1frame = 2blks DUP-ARQ
ARTRAC 2  |   |ITA2   |   |    |      |          |     | = 2blks of 32bits
          |   |       |   |    |      |          |     |1blk is 5bit cksum +
          |   |       |   |    |      |          |     | 3x8bit chars + 00
MERLIN/   | 5 |ITA2   | 48|111 | 485.4|          |228.7|1 blk = 2id + 30data+
ALIS/RSARQ|   |       |   |    |      |          |     | 16crc.
          |   |       |   |    |      |          |     |1ack blk = 16bits
PACTOR    | 8 |ITA5   | 96| 125| 1250 | 96/12/17 | 100 |*IRS is 12bits and
          |   |       |192| 250| 1250 |192/24*/32| 200 |ALWAYS sent @100bd
G-TOR     | 8 |ITA5   | 21|    |  240 |192/16/32 | 100 |
          |   |       | 45|    |  240 |          | 200 |
          |   |       | 69|    |  240 |          | 300 |

                 Asynchronous Data Block System - Table 5-B

         +-------------------------------------------- character size (bits)
         |  +----------------------------------------- alphabet in use
         |  |     +----------------------------------- block size (chars)
         |  |     |      +---------------------------- block size (bits)
         |  |     |      |      +--------------------- block tx time (mS)
         |  |     |      |      |       +------------- block breakdown (chars)
         |  |     |      |      |       |           +- most commonly found baud
         v  v     v      v      v       v           v  comments
HC-ARQ  |5|ITA2|  38 |  174  |  725 |4 char sync, |240| All packets sent with no
        | |    |     |       |      |5*30 chars,  |   | timing restraints. Data
        | |    |     |       |      |4 char CRC   |   | packet can be sent at
        |5|ITA2|  68 |  324  | 1350 |4 char sync, |240| any time after a rx'ed 
        | |    |     |       |      |5*60 chars,  |   | ACK from other station.
        | |    |     |       |      |4 char CRC   |   | Is therefore "Asynch".
        |5|ITA2| 188 |  924  | 3850 |4 char sync, |240| Packet length usually
        | |    |     |       |      |5*180 chars  |   | data chars + 8 chars
        | |    |     |       |      |4 char CRC   |   | overhead (4 header+4CRC)
PACKET/ |8|ITA5|8-264|64-2112|21-704|1 start flag,|300| Overhead is fixed at 8 
AX25    | |    |     |       |      |3 address,   |   | bytes.  Data block = 0
        | |    |     |       |      |1 control 0- |   | to 256 bytes
        | |    |     |       |      |256 data chrs|   |
        | |    |     |       |      |2 CRC bytes  |   |
        | |    |     |       |      |and end flag |   |

                 Asynchronous Bit Stream Systems - Table 5-C

          char  using
          size  alphabet  characteristics
BAUDOT   |5 bit|ITA2     |1 start,5 data, 1, 1.5, or 2 stop (exact stop bit
         |     |         |length can vary) 1 char = 7, 7.5, 8 bits
ASCII    |x bit|ITA5     |1start,5,6,7 data bits(x), 1 stop + 1p (optional)
         |     |         |1 char = 8,9 or 10bits/p bit = none,even or odd
BAUDOT/  |5 bit|ITA2     |2 ch, same speed ea. ch, 4 frequency, async
F7BBN    |     |         |

                 Synchronous Bit Stream Systems - Table 5-D

            +---------------------------------------------- char size (bit)
            |       +-------------------------------------- using alphabet
            |       |       +------------------------------ repetition cycle
            |       |       |    +------------------------- characteristics
            v       v       v    v
ARQ-N     | 7|ITA2P    | 4/8 |No inverted char every 4 of 8 char
ARQ-E/    | 7|ITA2P    | 4/8 |every 4th/8th char inverted which marks it
ARQ1000D  |  |         |     |as the 1st char of that block of 4 of 8 chars 
ARQ-E3    | 7|ITA3     | 4/8 |see ARQ-E
ARQ-M2-242| 7|ITA3     |4/5/8|a-ch erect, b-ch invert, char interleaved
       342| 7|ITA3     | 4/8 |a-ch erect, b-ch invert, char interleaved
ARQ-M4-242| 7|ITA3     |4/5/8|a/c-ch char interleaved a/b c/d bit interleave
          |  |         |     |a-ch erect b/c/d invert
       342| 7|ITA3     | 4/8 |a-ch erect, b-ch invert a/b chars interleaved
          |  |         |     |c-ch invert d-ch erect  a/b c/d bit interleave
AUTOSPEC  |10|ITA2 + 5p|     |1 char = 10 bits, 5bits of ITA2, 5 parity bits 
SPREAD    |10|ITA2 + 5p|     |1 char = 10 bits w/ea. char interleaved over 
          |  |         |     |11,21 or 51 bits
81-81     |12|CYR M2   |     |1 frame = 12 bits. 2-ch (bauds 73,81)
          |  |         |     |1 frame =  6 bits. 1-ch (bauds 36.5,40.5)
CIS-11    | 5|CYR M2   |     |1 frame = 11bits. 5 M2 char + 2state + 4p
          |  |         |     | M2 char: in reverse order. 2state bits define
          |  |         |     |  system state and alphabet.
CIS-14    | 5|CYR M2   |     |1 frame = 14bits. 2-ch bit interleave
          |  |         |     |frame:a1B1a2B2a3B3a4B4a5B5a6B6p1p2(2*6bits+2p)
          |  |         |     |a-ch:a2-6 b-ch:B2-6 a1B1=state (IDLE/TFC)
          |  |         |     | p1p2=error correction
          |  |         |     |1 frame = 28bits. CIS-14 variant
DUP-FEC-2 | 5|ITA2 or  |     |1 frame = 32bits. 5bit CRC used.
DUP-FEC   |  | ITA5    |     |
FEC-A/    | 7|ITA2P    |     |data bits+p bits interleaved. Parity created
FEC100A   |  |         |     |by shift register. 2 known lengths: 71 and 127
HNG-FEC   |15|15 bit   |     |1st 5bits ITA-2 with bits 1 and 5 inverted +
          |  |         |     |10bits error correction. interleave of 64bits, 
          |  |         |     |each new char starts 15bits after preceding char
POL-ARQ   | 7|CCIR476  |4/5/6|Similar to ARQ-N but using CCCIR476 alphabet
ROU-FEC/  |16|16 bit   |     |interleave of 128bits, new char starts 16bits
RUM-FEC   |  |         |     |from preceding char. Bit masking used (10,15,31)
SI-FEC/   | 7|ITA3     |     |each char inverted and repeated 15 chars later,
FEC-S/    |  |         |     |or 1050ms, similar to ARQ-M2-242
FEC1000S  |  |         |     |
SITOR-B/  | 7|CCIR476  |     |char interleaved, each char simply repeated
NAVTEX    |  |         |     |after 350ms (5 chars/35 bits later)
TORG-10/11|11|ITA2     |     |1 frame = 11 bits: 5 data+2sync+4p. See CIS-11
                 Multi-tone/MFSK/PSK Systems - Table 5-E

             +---------------------------------- modulation
             |    +----------------------------- # of tones 
             |    |        +-------------------- tone shift/arrangement 
             |    |        |           +-------- tone shift/spacing (Hz)
             |    |        |           |    +--- bps(FSK) / symbol/sec(PSK)
             v    v        v           v    v    comments
PICCOLO    |MFSK| 6| 5*20Hz tone3-8 |  20 |  20 |1 char -> 2 tones, ea 50ms
 MK6       |    |  |                |     |     |so 1 char = 100ms. 7.5 unit
           |    |  |                |     |     |ITA2 gives 75 baud throughput
           |    |12|11*20Hz tone0-11|  20 |  20 |ITA5 version.
PICCOLO    |MFSK| 6| 5*40Hz         |  40 |  40 |special alphabet in use
 MK10      |    |  |                |     |     |1 char -> 2 tones, ea 25ms
COQUELET 8 |MFSK| 8|7*26.7Hz tone1-8| 26.7| 26.7|1 char = 2 consecutive tones
           |    |  |                |     |     |ea 37.5ms. 1 char is 75ms
COQUELET 13|MFSK|13|8*30Hz tone1-8 +|  30 | 13.3|1 char = 2 consecutive tones
           |    |  |4*30Hz tone9-12 |     |     |ea. 75ms. 1 char is 150ms
CROWD36    |MFSK|36|35*40Hz tone1-36|  40 |  40 |3 groups of 10+11+11 tones
           |    |  |                |     |  10 |tones 1,12,24,36 rarely used
           |    |  |                |     |     |1 of 32 tones=1 of 32 ITA2 chars
           |    |  |                |     |     |1 tone = 100ms@10bps
           |    |  |                |     |     |1 tone =  25ms@40bps
MIL188     |MFSK| 8|7*250Hz         | 250 |     |1 sym = 8ms
TT2300b/   |MFSK| 8|7*200Hz         | 200 | 100/|100bd gives 300bps throughput
TPLEX      |    |  |                |     | 200 |200bd gives 600bps throughput
           |    |  |                |     |     |1 tone is 5ms@100bd 10ms@200bd
LINK-11    |QPSK|15|14*110Hz        | 110 |     |1 doppler tone @605Hz offset
           |    |  | tone 1@935Hz   |     |     |1 sync tone @2915Hz offset
LESW/LINK11|8PSK| 1|0*1800Hz        |   0 |     |data rates up to 4800bps
Single Tone|    |  |                |     |     |1 packet=192bits+64bits sync
Waveform   |    |  |                |     |     | 256bits=80ms   +26.67ms
MERLIN/    |MFSK| 8|7*240Hz tone1-8 | 240 | 240 |240sym/s or 720b/s 
ALIS-2     |    |  |                |     |     |
MS5 Russian|QPSK|12|11*200Hztone1-11| 200 | 100 |1 pilot tone @3300Hz
Vocoder    |    |  | tone 1@700Hz   |     |     |(rare: 3600Hz)
CLOVER     |PSK | 4|3*125Hz         | 125 |31.25|Supp: BPSM/125bps QPSM/250bps
           |    |  |                |     |     |      8PSM/375bps 16PSM/500bps
           |    |  |                |     |     |      8P2A/500bps 16P4A/750bps
           |    |  |                |     |     |Total bandwidth 500Hz
CLOVER-2000|PSK | 8|7*250Hz         | 250 |62.50|Supp: BPSM/500bps QPSM/1000bps
           |    |  |                |     |     |      8PSM/1500bps 8P2A/2000bps
           |    |  |                |     |     |      16P4A/3000bps
           |    |  |                |     |     |Total bandwidth 2kHz   
HF=Datalink|8PSK| 1|0*1440Hz        |   0 |     |Adaptive rates of 150,300,600,
           |    |  |                |     |     | 1200,1800 supported.   

                 Multi-tone/MFSK/PSK Systems - Table 5-E continued

             +---------------------------------- modulation
             |    +----------------------------- # of tones 
             |    |        +-------------------- tone shift/arrangement 
             |    |        |           +-------- tone shift/spacing (Hz)
             |    |        |           |    +--- bps(FSK) / symbol/sec(PSK)
             v    v        v           v    v    comments
4+4        |MFSK| 8|3*300Hz tone1-4 |     |     |1 channel is 150bps BPSK
           |    |  |1*450Hz Gap     |     |     |
           |    |  |3*300Hz tone5-8 |     |     |
39-tone    |PSK |39|38*56.25Hz      |56.25|2400 |tones 675Hz to 2812.5Hz
 modem     |    |  |                |     |     |1 doppler tone @393.75Hz
CODAN modem|QPSK|16|15*112.5Hz      |112.5|2400 |tones 656.25Hz to 2343.75Hz

                 TWINPLEX Parameters - Table 5-F

o CCIR476 alphabet, 1 char = 7bits
o 2 channels of 3 characters, 1 block = 6 chars
o Characters may be "erect" or "inversed" or "erect and inversed"
o 1 cycle = 450ms, 210ms tx 240ms rx
o Interleave is station selectable
o Channel decode is station selectable
o Frequency shift is station selectable

Interleave (lower case: ch1 UPPER CASE: ch2)    || Channel Decode Method
WORD -  abc ABC def DEF ghi GHI jkl             || * F7B-1  BBYY BYBY 
BIT  -  a1 A1 b2 B2 c3 C3 d4 D4 e5 E5 f6 F6     ||   F7B-2  BBYY BYYB
CHAR -  a A b B c C d D e E f F                 ||   F7B-3  BYBY BBYY
NONE -  abc def ghi jkl                         || * F7B-4  BYBY BYYB
        [normal SITOR sends interleave NONE]    ||   F7B-5  BYYB BBYY
--------------------+-----------+---------------+|   F7B-6  BYYB BYBY
 Frequency Offset   |  Shift    |  User         ||          ch.1 ch.2
 f1   f2   f3   f4  |           |               ||
-400 -200 +200 +400 |200/400/200|*              || B defined as:0/spc/start
-200 -85  +85  +200 |115/170/115|*Spain/Pakistan|| Y defined as:1/mrk/stop
-255 -85  +85  +255 |170/170/170| Dutch         ||
-150 -50  +50  +150 |100/100/100|               ||                  
-300 -100 +100 +300 |200/200/200|               ||
-200 -85  +85  +600 |115/170/515| Pakistan      || * commonly found
                    | 65/170/ 65|               ||
Usual defaults: 100bd, 115/170/115, Erect ch A, Invert ch B, word interleave

                 Notes on Alphabets - Table 5-G

o ITA2 is also referenced as Murray code.
o ITA3 is also called Moore code and each character is defined by the 35
  possible combinations of 3 ones and 4 zeros (3:4). 32 are the commonly
  defined character set and the remaining 3 are for error control and idle.
o ITA5 can be referred to as IRA.
o ITA5 is the ASCII alphabet and consists of 128 characters, controls,
  specials, numbers, lower case letters and upper case letters. This
  alphabet uses up to 7 bits and sometimes includes a 8th bit for parity.
o ITA2P is also referenced as ARQ1a by some manufacturers.
o ITA2P is 5 bit ITA2 converted to 7. A character is composed of 
  1 sync bit + 5 bit ITA2 char + parity. Sync bit is always 1 (except for
  idle and RQ), parity is odd.
o BAUER is a 10 bit alphabet, used by AUTOSPEC and SPREAD and is composed of
  a 5 bit ITA2 char + 5 bits parity. The parity arrangement is selectable and
  is often encountered with 5 bit ITA2 + 5 bit ITA2 repeated. In the even
  parity scenario the second 5 bits are inverted.

o 16 bit alphabet 0 is a 16 bit alphabet, used only by ROU-FEC
  16 bit alphabet 1 is a 16 bit alphabet mod 10, used only by ROU-FEC
  THESE ALPHABETS ARE LISTED IN Wavecom 4100 literature - no further details.

  The ROU-FEC alphabet is arranged with a single character length of 16 bits 
  and each 32 bit pattern equals one ITA2 character. Note that the actual ITA2 
  character bit pattern does not appear in the ROU-FEC character bit pattern. 
  This is because the alphabet is designed to obtain a maximum Hamming distance.

o FEC-A uses convolutional error correction with shift register lengths of 72
  or 128 bits. Every 2nd bit is used for convolutional error correction making
  each codeword 14 bits.

o With the introduction of the W4100DSP and W41pc, Wavecom has introduced
  some new alphabets:
    TASS Cyrillic
    Bulgarian ASCII
    Alphabet no. 403 used by Coquelet-8
    Alphabets no. 401 and 402 used by Coquelet-13
    Alphabets 80S and 82S used by Coquelet-82
o These alphabets are based on ITA2, a 5 bit alphabet.
    Cyrillic M2 
    Cyrillic M19  
    Arabic ATU-70 ("Baghdad 70")
    4th shift Arabic ATU-80 ("Baghdad 80")
    3rd shift Greek
    3rd shift Korean
    3rd shift Amharic
    3rd shift Thai

o 3rd shift Japanese is a 6 element code with start and stop signals used
  in Japan for their national TELEX network.

                 Code Tables                         B defined as:0/spc/start
                 -----------                         Y defined as:1/mrk/stop

           ITA2    Telex Mil.           ITA2P               SITOR 
No. Letter Figure  Fig.  Fig.   ITA2    ARQ1A     ITA3      CCIR476
--- ------ ------  ----- -----  -----   -------   -------   -------
 1   A      -      -     -      YYBBB   BYYBBBY   BBYYBYB   BBBYYYB
 2   B      ?      ?     ?      YBBYY   BYBBYYB   BBYYBBY   YBYYBBB
 3   C      :      :     :      BYYYB   BBYYYBB   YBBYYBB   BYBBBYY 
 4   D      $(1)   wru   $      YBBYB   BYBBYBY   BBYYYBB   BBYYBYB
 5   E      3      3     3      YBBBB   BYBBBBB   BYYYBBB   YBBYBYB
 6   F      %(2)   $     !      YBYYB   BYBYYBB   BBYBBYY   BBYBBYY
 7   G      &(2)   &     &      BYBYY   BBYBYYB   YYBBBBY   BYBYBBY
 8   H      #(2)   #     stop   BBYBY   BBBYBYY   YBYBBYB   BYYBYBB
 9   I      8      8     8      BYYBB   BBYYBBY   YYYBBBB   BYBBYYB
10   J      @(3)   bell  '      YYBYB   BYYBYBB   BYBBBYY   BBBYBYY
11   K      (      (     (      YYYYB   BYYYYBY   BBBYBYY   YBBBBYY
12   L      )      )     )      BYBBY   BBYBBYY   YYBBBYB   BYBYYBB
13   M      .      .     .      BBYYY   BBBYYYB   YBYBBBY   BYYBBBY
14   N      ,      ,     ,      BBYYB   BBBYYBY   YBYBYBB   BYYBBYB
15   O      9      9     9      BBBYY   BBBBYYY   YBBBYYB   BYYYBBB
16   P      0      0     0      BYYBY   BBYYBYB   YBBYBYB   BYBBYBY
17   Q      1      1     1      YYYBY   BYYYBYY   BBBYYBY   YBBBYBY
18   R      4      4     4      BYBYB   BBYBYBY   YYBBYBB   BYBYBYB
19   S      '(3)   '     bell   YBYBB   BYBYBBY   BYBYBYB   BBYBYYB
20   T      5      5     5      BBBBY   BBBBBYB   YBBBYBY   YYBYBBB
21   U      7      7     7      YYYBB   BYYYBBB   BYYBBYB   YBBBYYB
22   V      =      ;     ;      BYYYY   BBYYYYY   YBBYBBY   YYBBBBY
23   W      2      2     2      YYBBY   BYYBBYB   BYBBYBY   BBBYYBY
24   X      /      /     /      YBYYY   BYBYYYY   BBYBYYB   YBYBBBY
25   Y      6      6     6      YBYBY   BYBYBYB   BBYBYBY   BBYBYBY
26   Z      +(4)   "     "      YBBBY   BYBBBYY   BYYBBBY   BBYYYBB
27  cr      cr     cr    cr     BBBYB   BBBBYBB   YBBBBYY   YYYBBBB
28  lf      lf     lf    lf     BYBBB   BBYBBBB   YBYYBBB   YYBBYBB
29  ls      ls     ls    ls     YYYYY   BYYYYYB   BBBYYYB   YBYBBYB
30  fs      fs     fs    fs     YYBYY   BYYBYYY   BYBBYYB   YBBYBBY
31  sp      sp     sp    sp     BBYBB   BBBYBBB   YYBYBBB   YYBBBYB
32  idle(5)                     BBBBB   BBBBBBY   BBBBYYY   YBYBYBB
    RQ                                  YYYBBBB   BYYBYBB   YBBYYBB
    idle/beta                           YBBYBBY   BYBYBBY   BBYYBBY
    idle/alpha                          YBBBYYB   BYBYYBB   BBBBYYY
    CS1                                                     BYBYYBB
    CS2                                                     YBYBYBB
    CS3                                                     BYYBBYB
    CS4                                                     BYBYBBY
    CS5                                                     BYYBYBB

(1) "Who are you?" or British Pound symbol
(2) each country can assign
(3) can be switched
(4) sometimes " instead of +
(5) idle or 3rd shift


 digit 1st-->   0   1   2   3   4   5   6   7
 2 +-----------------------------------------
 n |         7  B   B   B   B   Y   Y   Y   Y     B defined as:0/mrk/stop
 d |         6  B   B   Y   Y   B   B   Y   Y     Y defined as:1/mrk/stop
 | |         5  B   Y   B   Y   B   Y   B   Y
 V | 4 3 2 1                                      bit ordering: 7654321
 0 | B B B B | NUL DLE SPC  0   @   P   `   p     Special Notes:
 1 | B B B Y | SOH DC1  !   1   A   Q   a   q     YYBBBBB 60 - back tic     (`)
 2 | B B Y B | STX DC2  "   2   B   R   b   r     BYBBYYY 27 - single quote (')
 3 | B B Y Y | ETX DC3  #   3   C   S   c   s     BYBYYBB 2C - comma        (,)
 4 | B Y B B | EOT DC4  $   4   D   T   d   t     BYBYYBY 2D - minus/dash   (-)
 5 | B Y B Y | ENQ NAK  %   5   E   U   e   u     YBYYYYY 5F - underline    (_)
 6 | B Y Y B | ACK SYN  &   6   F   V   f   v     YYYYYYB 7E - tilde        (~)
 7 | B Y Y Y | BEL ETB  '   7   G   W   g   w
 8 | Y B B B |  BS CAN  (   8   H   X   h   x
 9 | Y B B Y |  HT  EM  )   9   I   Y   i   y
 A | Y B Y B |  LF SUB  *   :   J   Z   j   z
 B | Y B Y Y |  VT ESC  +   ;   K   [   k   {
 C | Y Y B B |  FF  FS  ,   <   L   \   l   |
 D | Y Y B Y |  CR  GS  -   =   M   ]   m   }
 E | Y Y Y B |  SO  RS  .   >   N   ^   n   ~
 F | Y Y Y Y |  SI  US  /   ?   O   _   o  DEL

ACK - acknowledge            FF  - form feed
BEL - bell                   FS  - file separator
BS  - backspace              GS  - group separator
CAN - cancel                 HT  - horizontal tab
CR  - carriage return        LF  - line feed
DC1 - device control 1       NAK - negative acknowledge
DC2 - device control 2       NUL - null
DC3 - device control 3       RS  - record separator
DC4 - device control 4       SI  - shift in
DEL - delete                 SO  - shift out
DLE - data link escape       SOH - start of header
ENQ - enquiry or WRU         SPC - space
EM  - end of medium          STX - start of text
EOT - end of transmission    SUB - substitute
ESC - escape                 SYN - synchronous idle
ETB - end of block           US  - unit separator
ETX - end of text            VT  - vertical tab

References: Wavecom Elektronik AG, Wavcom W4100 product literature
            Wavecom Elektronik AG, W41PC User Manual and correspondance
            HOKA Electronics, Code 3 v5.00 decoder manual and correspondance
            HOKA Electronics, Code 30 v2.00 decoder manual and correspondance
            Klingenfuss Radioteletype Code Manual, 13th Edition


                 Crowd-36 Tones and Alphabet - Table 5-H

tone Freq(Hz) Ch/Fg  tone Freq(Hz) Ch/Fg  tone Freq(Hz) Ch/Fg
---- -------- -----  ---- -------- -----  ---- -------- -----
  1   -640    unperf  13   -160    G       25    320    D     
  2   -600    Q       14   -120    T       26    360    I     
  3   -560    X       15    -80    F       27    400    H     
  4   -520    W       16    -40    fs      28    440    ls     
  5   -480    V       17      0    M       29    480    S      
  6   -440    E       18     40    Y       30    520    O     
  7   -400    K       19     80    C       31    560    N     
  8   -360    space   20    120    cr      32    600    -     
  9   -320    B       21    160    Z       33    640    A     
 10   -280    R       22    200    U       34    680    P     
 11   -240    J       23    240    L       35    720               
 12   -200    ctl     24    280    ****    36    760          

 ctl  - control purposes
 fs   - figure shift
 ls   - letter shift
 **** - ref tone on 10bd op chat

Notes: * This is a preliminary table!
       * The output of the alphabet in use may vary at customer request.
       * Watch for tone 24 to stay up before 10bd operator chatter.

                 5/6 Tone Paging Parameter Tables - Table 5-I

European 5/6 tone systems - frequencies in Hz         * is Repeat tone
---------------------------------------------         = is Group tone

CCIR-1/2, CCITT, EIA, NATEL, ZVEI1/2, VDEW and EURO5 are 5 tone, EURO is 6 tone

                                ZVEI     DZVEI    DDZVEI
tone EEA      CCIR-1    CCIR-7  ZVEI-1   ZVEI-2            NATEL    EURO
 0  | 1981   | 1981   | 1981   | 2400   | 2200   | 2400   | 1633   |  979.8 |
 1  | 1124   | 1124   | 1124   | 1060   |  970   | 1060   |  631   |  903.1 |
 2  | 1197   | 1197   | 1197   | 1160   | 1060   | 1160   |  697   |  832.5 |
 3  | 1275   | 1275   | 1275   | 1270   | 1160   | 1270   |  770   |  767.4 |
 4  | 1358   | 1358   | 1358   | 1400   | 1270   | 1400   |  852   |  707.4 |
 5  | 1446   | 1446   | 1446   | 1530   | 1400   | 1530   |  941   |  652   |
 6  | 1540   | 1540   | 1540   | 1670   | 1530   | 1670   | 1040   |  601   |
 7  | 1640   | 1640   | 1640   | 1830   | 1670   | 1830   | 1209   |  554   |
 8  | 1747   | 1747   | 1747   | 2000   | 1830   | 2000   | 1336   |  510.7 |
 9  | 1860   | 1860   | 1860   | 2200   | 2000   | 2200   | 1477   |  470.8 |
10/A|=1055   |=2400   |=2400   |=2799.9 | 2599.9 |= 885   | 1633   |  433.9 |
11/B|  930   |  930   |  930   |  810   | 2799.9 |        |  600   |  400   |
12/C| 2246.9 | 2246.9 | 2246.9 |  970   |  810   |        |=1995   |  368.7 |
13/D|  991   |  991   |  991   |  886   |  886   |        | 2205   | 1153.1 |
14/E|*2110   |*2110   |*2110   |*2599.9 |*2400   |* 970   |*1805   |*1062.9 |
15/F| 2400   |    0   |    0   |    0   |    0   |        |    0   |    0   |
      40ms    100ms     70ms     70ms     70ms     70ms     70ms    100ms
                               Tone Duration

                                         11th root of 2
tone EIA      MODAT    CCITT    VDEW     Hi Freq  Lo Freq  
 0  |  600   |  637.5 |  400   | 2280   | 2400   | 1200   |
 1  |  741   |  787.5 |  697   |  370   | 2253   | 1127   |
 2  |  882   |  937.5 |  770   |  450   | 2116   | 1058   |
 3  | 1023   | 1087.5 |  852   |  550   | 1987   |  993   |
 4  | 1164   | 1237.5 |  941   |  675   | 1865   |  933   |
 5  | 1305   | 1387.5 | 1209   |  825   | 1751   |  876   |
 6  | 1446   | 1537.5 | 1335   | 1010   | 1644   |  822   |
 7  | 1587   | 1687.5 | 1477   | 1240   | 1544   |  722   |
 8  | 1728   | 1837.5 | 1633   | 1520   | 1450   |  725   |
 9  | 1869   | 1987.5 | 1800   | 1860   | 1361   |  681   |
10/A| 2151   |        | 1900   | 2000   |        |        |
11/B| 2432.9 |        | 2000   | 2100   |        |        |
12/C|=2010.1 |        | 2100   | 2200   |        |        |
13/D| 2292   |        | 2200   | 2300   |        |        |
14/E|* 459   |* 487.5 | 2300   | 2400   |        |        |
15/F|    0   |        |    0   |    0   |        |        |
      33ms     40ms    100ms    100ms     40ms     40ms
                               Tone Duration

  EEA    - Electronic Engineering Association, UK
  CCIR   - Comite Consultatif International de Radio
  ZVEI   - Zentralverband der Electrotechnischen Industrie, West Germany
  DZVEI  - Depressed ZVEI
  DDZVEI - Double Depressed ZVEI
  NATEL  - Scandinavian National Telephone
  Euro   - 6 tone Hi power AM paging in ECPT countries.
  EIA    - Electronics Industries Association, US - Motorola Metropage
  MODAT  - Motorola 7 tone ANI Status System
  REACH  - 2 to 5 tone selective call, ANI

Section 6. What decoders are available 

   This section will list most known units with information collected from a
   variety of open sources. They range from the professional high end units,
   through the hobbiest units, down to the public domain units. This grouping
   is purely the opinion of the compiler and is not meant to disparage any man-

   A professional unit is a unit that covers many modes, includes sophisticated
   analysis tools, and probably costs a lot of money. These units represent the
   cutting edge in decoder technology.  At this time we group Hoka, Wavecom and
   Universal as professional units.  The hobbiest units are those units that 
   include the most common modes, some tools for analysis and are a little more
   affordable. Public domain units are self explanatory but non the less valu-
   able as a stepping stone to a more sophisticated unit if you find the area
   of signals analysis intriguing.
   An attempt is made to completely list the complete capabilities and features
   of the professional units based on the latest literature from the manu-
   facturers. This is done because they provide the most for the money. 

   In the hobbiest units, an attempt is made to provide hilites for each unit.
   Keep in mind that it is impossible to own or test all the units mentioned
   here - nor would you want to. Many units provide the same capability and
   similiar tools and the decision to buy one unit over another will probably
   come down to cost. Another question to consider is whether or not "hobbiest"
   units can really be considered serious units for monitoring? If you have
   the desire to ferret out and identify digital signals then these units will
   have a high frustration factor because they don't include the wide selection
   of modes currently on the air or the necessary tools to analyse a signal. If
   marine, soviet, or amateur monitoring is what you are looking for then these
   units can be a cost effective selection.

   FAX and SSTV units are not covered in this document. Instead check out one
   of the best FAX/SSTV references on the net:

   This page is maintained by Marius Rensen and covers FAX technology, FAX
   transmission schedules and decoders. This page also includes SSTV related
   programs. See the SSTV information in Section 1-F of this document for 
   other net resources.

   Specifically this section covers the following data decoders:

      Professional Units             Manufacturer
      ----------------------------   ---------------------------------
new   M400v3/M450, M900v2 VF,        Universal (obsolete M-200F, M600A
      M1200v2, M8000v7                          M6000 and M-7000)
new   Code 3 Gold, Code 3, Code 30   Hoka
      W4010, W4050, W4100            Wavecom
new   W41PC, W4100DSP

      Hobbiest Units                 Manufacturer
      ----------------------------   ---------------------------------
      AEA PK-232MBX                  Advanced Electronic Applications
      AEA PK900                      Advanced Electronic Applications
new   NOTE: as of Nov 15 1996 AEA is Out of Business. Timewave will be
            taking over the AEA data and software product lines.  See 
   for further information.

      Air Master, Mode Master        Lowe
      ERA Microreader                ERA
      MCL 1100                       Momentum Communications
      PC/SWL                         Software Systems Consulting
      Franklin Converter             Logic Limited
      KAM+ Multi-Mode Controller     Kantronics
      MFJ462B stand alone reader     MFJ
      MFJ1214PC                      MFJ
      MFJ1278B data controller       MFJ
      BMK-MULTY v3.43                G4BMK
      P38                            HAL
      Personal Code Explorer         Microcraft Corporation

      Public Domain/Shareware        Manufacturer               Registration
      ----------------------------   ------------------------   ------------
      Hamcomm                        Trialware                  30.00
      JVFax                          Public Domain
new   FTV                            Trialware
new   RadioRaft                      Trialware                  28.00 

      Note: Trialware means the author lets you try a "lite" version
            before registring for the full version of the software.

      VHF Units                      Manufacturer
      ----------------------------   ------------------------
      Message Tracker v2.0           K&L Technology
      ACT1 ACARS                     Universal Radio
      Pager Datascope                JSoft Technologies
      ACARS Decoder                  Advanced Electronic Applications
                                     See Timewave note above.
new   PD203                          Trialware                  20.00 pds
new   KRACARS v1.2                   Freeware
new   WACARS v0.1                    Freeware

6-A. PROFESSIONAL UNITS                                      PROFESSIONAL UNITS

6-A.1 HOKA Decoders

Decoder:            Code 3 Gold

Level:              Intermediate

Synopsis:           The Code 3 Gold is the latest incarnation of the capable
                    Code 3 decoder software. Arriving in a newly repackaged 
                    interface, now fitting into a dongle stlye standard RF 
                    shielded serial connector. This interface needs no external
                    power supply, with all power coming directly from the PC 
                    serial port. Both 9 pin and 25 pin serial connectors are 
                    supported. For Windows 3.1 users, the software will run in
                    a DOS Window. This package is aimed at those who wish to
                    decode the systems found on the HF and VHF airwaves but if
                    you want to get into the underlying details you will find
                    that only the basic analysis tools are included. For more
                    advanced tools a Code 3 or Code 30 is recommended.

Modes Decoded:      Basic Code3 Gold handles VHF systems and the more common 
                    HF systems.  This includes ACARS/SITA, POCSAG (ALL known
                    baud speeds), DTMF, Packet (300+1200), Baudot, Ascii, 
                    Sitor ARQ/FEC, Pactor, Fax (FM and AM Meteosat) and SSTV 
                    (Martin 1 only).

                    The "SW Option" includes: Annex10, Hell, Morse, ARQ-S, 
                    ARQ-SWE, ARQ-E, ARQ-M2/4 (CCIR242/CCIR342), ARQ-N, ARQ-6, 
                    ARQ-E3, POL-ARQ, Twinplex, Artrac, F7BBN Baudot Twinplex,
                    FEC-A, FEC-S, Autospec, Spread, HC-ARQ, TORG10/11, ROU-FEC,
                    HNG-FEC, Coq8/13, Piccolo Mk6, GMDSS/DSC and SYNOP (AAXX/
                    BBXX with 10,000 stations)

Analysis Tools:     AutoClassification
                    ASCII Save to Disc
Extras Required:    PC with 386DX40 or more. 486 HIGHLY recommended.
                    VGA supported (SVGA supported with Tseng ET4000)

Supplier:           (US) Computer Aided Technologies, PO Box 18292,
                    Shreveport, LA 71138, USA  Tel: 318 636 1234
                    (NL) Hoka Electronics, Flessingsterrein 13,
                    NL-9665, BZ Oude Pekela, Netherlands Tel: +31 5978 12327

                    (UK) Multicomm 2000, Unit 3-4, 86 Cambridge Street, 
                    St. Neots, Cambridgeshire, PE19 1PJ. Tel/Fax: 01480 406770 
                                                      Intern'l +44 1480 406770


Decoder:            Hoka Code 3 (version 5)

Level:              Comprehensive, sophisticated decoder for Experts

Synopsis:           The Hoka Code 3 comes in two parts: an interface box
                    which connects to a free serial port of an IBM
                    compatible PC, and the software itself, on a 1.44Mb
                    3.5 inch PC diskette.  The hardware interface box now
                    contains a software controlled filter which improves
                    decoding performance over the previous version (v4).
                    Bandpass filter is automatically controlled in center
                    frequency and bandwidth for optimum setting depending
                    on the decoding module, baud speed and shift setting.
                    The decoder is implemented entirely in software which 
                    makes it extremely powerful together with a wealth of 
                    analysis tools, most of which are also included as 
                    standard.  This is probably the most powerful decoder 
                    for its price.  The user has practically complete control
                    over all important parameters for each mode decoded. Exotic
                    data systems are available as optional software modules, 
                    at extra cost.  Comprehensive on-screen diagnostics and 
                    system information are shown for each mode decoded.  Each 
                    module is chosen from a simple menu system with one-key 
                    commands to set or change system parameters.  There is even
                    an optional module (Auto Classification) which will
                    measure the system's baud speed and shift parameters,
                    analyse the bit pattern and jump into the correct decoding
                    module for the received data system!
                    Full Synoptic decoding of meteo AAXX and BBXX
                    codes is also available as an option.
Modes Decoded:      ARQ6-70
                    ARQ6-90 & 98
                    ARQ-N (built info ARQ-E module)
                    ARQ-M2-242/2 ch CCIR242
                    ARQ-M4-242/4 ch CCIR242 (Part of ARQ-M2-242 module)
                    ARQ-M2-342/2 ch CCIR342-2
                    ARQ-M4-342/4 ch CCIR342-2 (Part of ARQ-M2-242 module)
                    ASCII (ITA-5/IRA)
                    Baudot RTTY with Auto speed determination
                    Baudot F7BBN RTTY with Auto speed determination
                    COQUELET Mk I (13 tone) (Option "Specials")
                    COQUELET Mk II (8 tone) (Option "Specials")
                    CW with Auto speed determination (uses "Farnsworth" method)
                    DUP-ARQ ARTRAC
                    FAX 60, 90, 120, 240 LPM: 288, 352, 576 IOC B/W & 16 shade
                    FEC-A (with Error correction enabled)
                    FEC-A RAW (no Error correction)
                    GMDSS/DSC (Option "Specials")
                    HC-ARQ (Option "Specials")
                    HNG-FEC (Option "Specials")
                    AX.25 Packet 300 and 1200 Baud
                    PACTOR, including ICRC and UNHCR variants
                    PICCOLO Mark VI (Option "Specials")
                    ROU-FEC/RUM-FEC (Option "Specials")
                    SITOR-A RAW
                    SPREAD 11, 21, 51 (built into AUTOSPEC module)
                    SYNOP 'AAXX' and 'BBXX' decoding (Option "SYNOP")
                    TORG-10 & 11 (Option "Specials")

Analysis Tools:     Signal Spectrum "Analyser" with high precision Baud Rate
                    and Shift measurement
                    Calibrated Signal Oscilloscope (user selectable settings)
                    Signal "Autocorrelation Raw" (on raw audio components)
                    Signal "Autocorrelation Mod" (on modulated components)
                    Signal "Autocorrelation Bit" (on bit pattern component)
                    Text screen based "rough and ready" baud speed indicator
                    Text screen based mark/space ratio bias dist. indicator
                    Graphical bit stream viewer (fully user selectable)
                    Text screen based bit stream viewer with output to disk
                    Character Analysis Simplex (for Simplex ARQ systems)
                    Character Analysis Duplex (for Duplex ARQ and FEC systems)
                    Auto Classification

Extras Required:    IBM Compatible PC (80286 or 80386 CPU)
                    Mono or Colour Monitor
                    1 free serial port (for LF3 Interface connection)

Supplier:           (US) Computer Aided Technologies, PO Box 18292,
                    Shreveport, LA 71138, USA  Tel: 318 636 1234
                    (NL) Hoka Electronics, Flessingsterrein 13,
                    NL-9665, BZ Oude Pekela, Netherlands Tel: +31 5978 12327
                    (UK) Multicomm 2000, Unit 3-4, 86 Cambridge Street, 
                    St. Neots, Cambridgeshire, PE19 1PJ. Tel/Fax: 01480 406770 
                                                      Intern'l +44 1480 406770


Decoder:            Hoka Code 30 (version 2.6)

Level:              Comprehensive, VERY sophisticated decoder for Experts

Synopsis:           Arguably the King of Decoders!  The decoder
                    consists of a card which is inserted into a free 8
                    or 16 bit slot in an IBM compatible PC, together
                    with the decoding software on a 1.44Mb diskette.
                    The decoder board is high-quality, RF screened and
                    makes use of Digital Signal Processing (DSP)
                    techniques.  Because of DSP technology, the Code 30
                    will deal with any traditional system plus complex
                    systems using Phase Shift Keying (PSK) and the like.
                    Its power and flexibility, due to DSP and software
                    based modules, means that many government agencies and
                    military surviellance units make use of the Code 30.
Modes Decoded:      ARINC ANNEX10 Selcal (aircraft selcals)
                    ARQ6-90 & 98
                    ARQ-N (built info ARQ-E module)
                    ARQ-M2-242/2 ch CCIR242
                    ARQ-M4-242/4 ch CCIR242 (Part of ARQ-M2-242 module)
                    ARQ-M2-342/2 ch CCIR342-2
                    ARQ-M4-342/4 ch CCIR342-2 (Part of ARQ-M2-242 module)
                    ASCII (ITA-5/IRA)
                    Baudot RTTY with Auto speed determination
                    Baudot F7BBN RTTY with Auto speed determination
                    COQUELET Mk I (13 tone) (Option "Specials")
                    COQUELET Mk II (8 tone) (Option "Specials")
                    COQUELET-8 FEC
                    CW with Auto speed determination (uses "Farnsworth" method)
                    DUP-ARQ ARTRAC
                    FAX 60, 90, 120, 240 LPM: 288, 352, 576 IOC B/W and
                        256 shade at 1024x768. Also Meteosat AM demod.
                    FEC-A (with Error correction enabled)
                    FEC-A RAW (no Error correction)
                    GMDSS/DSC (Option "Specials")
                    HC-ARQ (Option "Specials")
                    HNG-FEC (Option "Specials")
                    AX.25 Packet 300 and 1200 Baud
                    PACTOR, including ICRC and UNHCR variants
                    PICCOLO Mark VI (Option "Specials")
                    ROU-FEC/RUM-FEC (Option "Specials")
                    SITOR-A RAW
                    SPREAD 11, 21, 51 (built into AUTOSPEC module)
                    SYNOP 'AAXX' and 'BBXX' decoding (Option "SYNOP")
                    TIME (DCF77) - set PC date/time to DCF77 time.
                    TORG-10 & 11 (Option "Specials")

VHF Modes Decoded:  ACARS/SITA
                    CCIR 1 Selcal (Option "VHF")
                    CCIR 7 Selcal (Option "VHF")
                    CCITT Selcal (Option "VHF")
                    CTCSS all standard frequencies (Option "VHF")
                    DCS (PL) all standard codes (Option "VHF")
                    DTMF (Option "VHF")
                    EEA Selcal (Option "VHF")
                    EIA Selcal (Option "VHF")
                    EURO Selcal (Option "VHF")
                    NATEL Selcal (Option "VHF")
                    Tone AutoClassification (Option "VHF")
                    Pocsag/Super Pocsag
                    VDEW Selcal (Option "VHF")
                    ZVEI 1 Selcal (Option "VHF")
                    ZVEI 2 Selcal (Option "VHF")

Demodulators:       OOK, BFSK, BFEK, MFSK, MFEK (up to 40 tones), 2DPSK,
                    4DPSK, BPSK, QPSK, OQPSK (MSK). Diversity can also be
                    selected. Both input signals are sampled many times PER
                    ELEMENT and best signal chosen in real-time.

Analysis Tools:     Signal Spectrum "Analyser" with high precision Baud Rate
                        and Shift measurement
                    Audio Oscilloscope with zoom function
                    Signal "Autocorrelation Raw" (on raw audio components)
                    Signal "Autocorrelation Mod" (on modulated components)
                    Signal "Autocorrelation Bit" (on bit pattern component)
                    Text screen based "rough and ready" baud speed indicator
                    Text screen based mark/space ratio bias dist. indicator
                    Graphical bit stream viewer (fully user selectable)
                    Text screen based bit stream viewer with output to disk
                    Character Analysis Simplex (for Simplex ARQ systems)
                    Character Analysis Duplex (for Duplex ARQ and FEC systems)
                    Auto Classification
                    High precision Audio Spectrum Analyser. 3 zoomed displays
                        down to +/-250Hz.
                    Audio Spectrum Waterfall display. 3 zoomed displays down
                        to +/-250Hz.
                    Phase Spectrum Analyser
                    Phase Oscilloscope
                    Phase Plane (aka "Vector scope")
                    Straddle (X tuning screen for FSK's)

                    Save raw digitized/sampled audio to Disk File - 7MB of
                        extended RAM equates to approx 15 minutes "record time"
                    Save Decoded text to Disk File

Alphabets (ITA2 variants):
                    Standard International
                    US Military
                    National Scandinavian
                    3rd shift Greak (Optional)
                    M19 Cyrillic (Optional)
                    M19 Latinized (Optional)
                    M2 3rd Shift Cyrillic (Optional)
                    M2 3rd Shift Latinized (Optional)
                    Hebrew (Optional)
                    Amateur upper/lower case
                    Arabic ATU-70 (Optional)
                    Arabic ATU-70 Latinized (Optional)
                    Arabic ATU-80 4th shift (Optional)
                    Arabic ATU-80 4th shift Latinized (Optional)
                    Farsi (Optional)

Extras Required:    IBM Compatible PC (at least 80386 CPU - '486 recommended)
                    Mono or Colour Monitor

Supplier:           (US) Computer Aided Technologies, PO Box 18292,
                    Shreveport, LA 71138, USA  Tel: 318 636 1234
                    (NL) Hoka Electronics, Flessingsterrein 13,
                    NL-9665, BZ Oude Pekela, Netherlands Tel: +31 5978 12327
                    (UK) Multicomm 2000, Unit 3-4, 86 Cambridge Street, 
                    St. Neots, Cambridgeshire, PE19 1PJ. Tel/Fax: 01480 406770 
                                                      Intern'l +44 1480 406770

6-A.2 Wavecom Decoders

Decoder:            WaveCom W4010 (version 5)

Level:              Comprehensive, intermediate level decoder

Synopsis:           The first comprehensive decoder for the amateur as
                    well as professional user.  Now being phased out in
                    favour of the more up-to-date W4050 but still
                    widely available on the second hand market. Again,
                    a self-contained unit requiring a composite monitor for
                    the control, and incoming text displays.  Like its
                    W4100 bigger brother, this decoder again sports
                    just about every mode that is in regular use on HF
                    plus a good array of analysis tools.
                    Software and modes decoded are held in a number of
                    EPROMs contained in the machine, amking for simple update.

Modes Decoded:      Baudot RTTY Auto speed determination
                    CW Auto speed determination
                    ASCII (ITA-5/IRA)
                    AX.25 Packet 300 and 1200 Baud
                    FAX 60, 90, 120, 240 LPM: 288, 352, 576 IOC

Analysis Tools:     Speed/Baudrate Determination
                    IAS Baudrate determination
                    Shift Measurement
                    System Alphabet and Bit analysis
                    Unshift On Space (UOS)
                    Multiple Scroll Inhibit

Extras Required:    Composite Video Monitor

Supplier:           WaveCom Nachrichtentechnik AG, Badenerstrasse 122,
                    CH-8434, Kaiserstuhl, Switzerland.  Tel: 1858 0200

Decoder:            WaveCom W4050 (Preliminary Info at March 1995)
                                  Still delayed as of this writing by the 
                                  introduction of the W41PC

Level:              Comprehensive, VERY sophisticated decoder for Experts

Synopsis:           Will this be the challenger to the Hoka Code 30 and
                    knock it off its throne as "King of Decoders"?
                    This decoder is expected to be released at any time
                    now and will basically be a new W4100.  A new PC
                    control system is also planned to be available at
                    the same time as the decoder.  Full use will be made
                    of Digital Signal Processing (DSP) technology allowing
                    for the decoding of traditional, and more complex
                    systems, like DPSK, QPSK etc.  Otherwise just like
                    the W4100 with a very powerful suite of analysis
                    tools and modes that can be decoded.

Modes Decoded:      Baudot RTTY Auto speed determination
                    CW Auto speed determination
                    TORG-10 & 11
                    ASCII (ITA-5/IRA)
                    SPREAD 11, 21, 51
                    ARQ-6-90 & 98
                    PACTOR, including ICRC variants
                    Piccolo Mark VI and Mark 12
                    Coquelet Mark I
                    AX.25 Packet 300 and 1200 Baud
                    FAX 60, 90, 120, 240 LPM: 288, 352, 576 IOC
                    Meteosat Satellite FAX
                    Meteo Synoptic Decoder (Optional)

Analysis Tools:     Fast Fourier Transform Speed/baudrate Determination
                    Real-Time Spectrum Analyser
                    IAS Baudrate determination
                    Fast Fourier Transform Shift Measurement
                    Autocorrelation of signal and data
                    System Alphabet and Bit analysis
                    Bit Length Analysis
                    Automatic Recognition of all systems decoded

Extras Required:    VGA Monitor

Supplier:           WaveCom Nachrichtentechnik AG, Badenerstrasse 122,
                    CH-8434, Kaiserstuhl, Switzerland.  Tel: 1858 0200

Decoder:            WaveCom W4100 (version 2.5.09)

Level:              Comprehensive, VERY sophisticated decoder for Experts

Synopsis:           Until the Hoka Code 30 came along, this was probably the 
                    analog decoder of choice for professional monitors in 
                    military and government agencies.  The W4100 is a 19 inch 
                    rack mounting machine, self-contained unit which requires 
                    a VGA monitor as a display.  If you want to build your own
                    decoders, software can be loaded into the machine via a 
                    front panel mounted 3.5 inch disk drive.  Like the Hoka
                    decoders, a comprehensive set of signal analysis tools 
                    come as standard and the array of systems that the machine 
                    can decode is equally impressive.  The display can also 
                    show text in English, Arabic, Cyrillic, and Greek directly.

Modes Decoded:      Baudot RTTY Auto speed determination
                    CW Auto speed determination
                    TORG-10 & 11, SITOR-A, SITOR-B, ASCII (ITA-5/IRA)
                    SI-ARQ, ALIS (RS-ARQ), FEC-A, FEC-S, SI-FEC, SPREAD 11, 
                    21, 51, AUTOSPEC, DUP-ARQ, TWINPLEX, ARQ-6-90 & 98,
                    SWED-ARQ, ARQ-E, ARQ-E3, POL-ARQ, ARQ-M2, ARQ-M4, ARQ-N
                    PACTOR, including ICRC variants, Hellschreiber
                    Piccolo Mark VI and Mark 12, Coquelet Mark I,
                    ROU-FEC/RUM-FEC, HC-ARQ, HNG-FEC
                    AX.25 Packet 300 and 1200 Baud
                    FAX 60, 90, 120, 240 LPM: 288, 352, 576 IOC
                    Meteosat Satellite FAX
                    Meteo Synoptic Decoder (Optional)
                    POCSAG, GOLAY, ATIS, FMS-BOS, INFOCALL

Analysis Tools:     Fast Fourier Transform Speed/baudrate Determination
                    Real-Time Spectrum Analyser
                    IAS Baudrate determination
                    Fast Fourier Transform Shift Measurement
                    Autocorrelation of signal and data
                    System Alphabet and Bit analysis
                    Bit Length Analysis
                    Automatic Recognition of all systems decoded

Extras Required:    VGA Monitor

Supplier:           WaveCom Nachrichtentechnik AG, Badenerstrasse 122,
                    CH-8434, Kaiserstuhl, Switzerland.  Tel: 1858 0200

Decoder:            WaveCom W4100DSP

Level:              Comprehensive, VERY sophisticated decoder for Experts

Synopsis:           The W4100DSP is the successor to the analog W4100 that
                    makes extensive use of DSP technology, incorporating 2
                    Motorola DSP56002-66 DSP engines and a TI TMS34010-50 for
                    graphics handling. The W4100 will continue to be produced.
                    According to Wavecom this unit is capable of handling over
                    60 different modes in the HF, VHF, UHF and SHF spectrum.
                    The unit can be remotely controlled and incorporates
                    software from SHOC and Klingenfuss and runs under Win 95.

Modes Decoded:      ALIS ARQ-E ARQ-E3 ARQ-M2 242/342 ARQ-M4 242/342 ARQ-N
                    ARQ6-90 ARQ6-98 ASCII AUTOSPEC BAUDOT BR6028 CIS-11 CIS-14
                    DUP-ARQ-2 DUP-FEC-2 FEC-A G-TOR HC-ARQ HNG-FEC PACTOR 1-5
                    SPREAD-11 SPREAD-21 SPREAD-51
                    SSTV (Martin M1/M2, Scotty S1/S2 and Robot 36/72)

                    ACARS ATIS CALSEL ERMES FMS-BOS GOLAY MPT1327/1343
                    PACKET RADIO POCSAG
                    SELCALL (ZVEI-I, ZVEI-II, EIA, CCIR-I, EEA/CCIR-7, CCITT,
                     VDEW, NATEL, EURO, DTMF, ANNEX 10/SELCAL)
                    METEOSAT (AM Satellite weather fax)
                    NOAA-GEOSAT    (AM Satellite weather fax)
                    Inmarsat C and M systems are in development

Analysis Tools:     Real-time Spectrum
                    Real-time Waterfall
                    Baud rate
                    Shift measurement
                    Mode/Code analysis
                    Bit Length analysis
Extras Required:    

Supplier:           WaveCom Nachrichtentechnik AG, Hammerstrasse 8,
                    CH-8180, Buelach, Switzerland.  Tel: +41 1 872 70 60
Decoder:            WaveCom W41pc (version 2.2)

Level:              Comprehensive, VERY sophisticated decoder for Experts

Synopsis:           The W41pc is a DSP based plug-in card for the IBM PC and
                    uses the windows front-end to drive the board under Win95 
                    or NT 95. Simultaneous operation of up to 8 cards is 
                    supported allowing for the monitoring of up to 8 different
                    transmissions on the same PC. Decoding of over 50 modes
                    spanning the HF, VHF, UHF and SHF is supported. Remote
                    control is supported thru a combination of software from
                    SHOC (Radio Manager) and Klingenfuss (frequency database).
                    The W41PC has the added capability of supporting the 
                    development of unique decode modes. The W41PC source code
                    (available to official organizations or other authorized
                    users) allows complete control over all parameters.

Modes Decoded:      ALIS ARQ-E ARQ-E3 ARQ-M2 242/342 ARQ-M4 242/342 ARQ-N
                    ARQ6-90 ARQ6-98 ASCII AUTOSPEC BAUDOT BR6028 CIS-11
                    CIS-14 CIS-36 COQUELET-8 COQUELET-13 COQUELET-82 CW-MORSE
                    DUP-ARQ DUP-ARQ-2 DUP-FEC-2 FEC-A G-TOR HC-ARQ HNG-FEC
                    SITOR-AUTO SITOR-FEC SPREAD-11 SPREAD-21 SPREAD-51
                    SSTV (Martin M1/M2, Scotty S1/S2 and Robot 36/72)

                    ACARS ATIS CALSEL ERMES FMS-BOS GOLAY MPT1327/1343
                    PACKET RADIO POCSAG
                    SELCALL (ZVEI-I, ZVEI-II, EIA, CCIR-I, EEA/CCIR-7, CCITT,
                     VDEW, NATEL, EURO, DTMF, ANNEX 10/SELCAL)
                    METEOSAT (AM Satellite weather fax)
                    NOAA-GEOSAT    (AM Satellite weather fax)
                    Inmarsat C and M systems are in development

Analysis Tools:     Real-time Spectrum
                    Real-time Waterfall
                    Baud rate
                    Shift measurement
                    Mode/Code analysis
                    Bit Length analysis
Extras Required:    PC compatible (probably Pentium class) w/Win95 or NT

Supplier:           WaveCom Nachrichtentechnik AG, Hammerstrasse 8,
                    CH-8180, Buelach, Switzerland.  Tel: +41 1 872 70 60

                    Klingenfuss Publication, Hagenloher Str. 14
                    D-72070 Tuebingen, Germany. Tel: +49 7071 62830

6-A.3 Universal Decoders

Decoder:            Universal M400 (version 3)
                    Universal M450

Description:        Entry level decoder for Beginners

Synopsis:           An easy-to-use decoder with most of the common modes
                    found on both VHF, UHF and HF. Self-contained unit with
                    a two line LCD display providing for 40 characters of 
                    text, there is also an 8000 character scrollable buffer
                    which holds incoming text for review later. Housed in a
                    metal case. Universal Radio also supply an IBM computer
                    control and text display option called the CI-400
                    costing around USD100.

                    The M450 is the newest incarnation of this decoder. All
                    modes supported with the M400v3 are supported with the
                    M450. The M450 includes a serial port for connection
                    to PC so a separate interface for text capture is not

Modes Decoded:      Baudot RTTY 45, 50, 57, 75, 100 Baud
                    Baudot RTTY 60, 66, 75, 100, 132 WPM
                    ASCII (ITA-5/IRA) 75, 110, 150 Baud
                    FEC-A 96, 144 Baud
                    FAX 120 LPM, 576 IOC
                    POCSAG & SUPER POCSAG (512, 1200 and 2400bd)
                    DTMF 16 digits
                    CTCSS (PL) 41 standard tones
                    DCS (DPL) 104 standard codes

Analysis Tools:     LED Indicators for Mark, Space, Input and Data

Extras Required:    Graphics compatible parallel printer (for FAX)

Supplier:           (US) Universal Radio, 6830 Americana Parkway,
                    Reynoldsburg, Ohio, OH 43068, USA  Tel: 614 866 4267
                    (UK) Martin Lynch, 140-142 Northfield Avenue,
                    Ealing, London, W13 9SB, United Kingdom
                    Tel: +44 181 566 1120

Decoder:            Universal M900-VF (version 2)

Discription:        Entry level decoder for Beginners

Synopsis:           Easy to use decoder that covers all the main HF
                    data modes.  Basically an M400 unit without the VHF
                    stuff and without the self contained display.  This
                    one does cover CW (Morse) though.

Modes Decoded:      Baudot RTTY 45, 50, 75 Baud
                    Baudot RTTY 60, 66, 100 WPM
                    CW 6 to 35 WPM (auto speed determination)
                    FEC-A 96, 144 Baud
                    FAX 60, 120, 240 LPM, 
                        288 or 576 IOC

Analysis Tools:     LED Indicators for Mark, Space, Error, Data,
                    Squelch, and Limiter.  User controls for
                    Normal/Reverse tones, Squelch setting, Change Case,
                    Shift Up, Shift Down and Unshift on Space (UOS).

Extras Required:    Video Monitor (mono, composite video)
                    Graphics compatible parallel printer (for hard copy)
                    12V DC Power Supply
Supplier:           (US) Universal Radio, 6830 Americana Parkway,
                    Reynoldsburg, Ohio, OH 43068, USA  Tel: 614 866 4267
                    (UK) Martin Lynch, 140-142 Northfield Avenue,
                    Ealing, London, W13 9SB, United Kingdom
                    Tel: +44 181 566 1120

Decoder:            Universal M1200v2

Level:              Intermediate-level decoder for HF and VHF systems

Synopsis:           This decoder is comes on a full-size PC card to be
                    inserted into an IBM compatible machine.  The
                    control software is supplied on a 3.5 inch PC
                    diskette.  Comprehensive on-screen status information
                    and basic diagnostics are included.

Modes Decoded:      Baudot RTTY 20 to 250 Baud, auto speed determination
                    CW 5 to 90 WPM, auto speed determination
                    ASCII (ITA-5/IRA) 75, 110, 150, 300, 600, 1200 Baud
                    ARQ-M2 86, 96, 100 Baud
                    ARQ-M4 172, 192, 200 Baud
                    ARQ-E 48, 64, 72, 86, 96, 144, 192 Baud
                    ARQ-E3 48, 64, 72, 86, 96, 100, 192, 200 Baud
                    ARQ-6-90 200 Baud
                    FEC-A 96, 144, 192 Baud
                    FAX 60, 90, 120, 240 LPM: 288, 440 or 576 IOC
                    AX.25 Packet 300, 1200 baud
                    POCSAG 1200, 2400
                    CTCSS 41 standard frequencies
                    DCS (PL) 104 standard codes
Analysis Tools:     On-screen tuning and staus information.  Multiple
                    Scroll Inhibit, Over-print Inhibit, Automatic
                    Threshold Control, Databit and Literal modes.
                    False colour and zoom for FAX.  Incoming text can
                    be saved to disk.  User programmable memories and
                    on-screen datascope.

Extras Required:    IBM compatible PC with VGA or EGA colour or mono monitor 
Supplier:           (US) Universal Radio, 6830 Americana Parkway,
                    Reynoldsburg, Ohio, OH 43068, USA  Tel: 614 866 4267
                    (UK) Martin Lynch, 140-142 Northfield Avenue,
                    Ealing, London, W13 9SB, United Kingdom
                    Tel: +44 181 566 1120

Decoder:            Universal M8000 (version 7)

Level:              Professional-grade, sophisticated decoder for Experts

Synopsis:           Stand-alone decoder much used by professional and
                    semi-professional monitoring agencies around the
                    world.  Decodes just about anything that you'll
                    hear on VHF or HF, but not quite in the same league
                    as the Hoka PC-based systems or the Wavecom family.
                    Can be fully controlled by a computer or terminal.
                    Ten memories can be used to store favourite
                    operating settings.  Housed in a standard 19 inch
                    rack mount cabinet. 

Modes Decoded:      Baudot RTTY 20 to 250 Baud, auto speed determination
                    CW (auto speed determination)
                    ASCII (ITA-5/IRA) 75, 110, 150, 300, 600, 1200 Baud
                    VFT (FDM) 8, 12, 16, or 24 channels
                    Piccolo 6 tone
                    ARQ-M2 86, 96, 100 Baud
                    ARQ-M4 172, 192, 200 Baud
                    ARQ-E 48, 64, 72, 86, 96, 144, 192 Baud
                    ARQ-E3 48, 64, 72, 86, 96, 100, 192, 200 Baud
                    ARQ-S 4, 5, 6, 7 character blocks
                    ARQ-6-90 200 Baud
                    SWED-ARQ 3, 9, 22 character blocks
                    FEC-A 96, 144, 192 Baud
                    FEC-S 96, 100, 144, 192, 200 Baud
                    FAX 60, 90, 120, 240 LPM: 288 or 576 IOC
                    AX.25 Packet 300, 1200 baud
                    PACTOR 100, 200 Baud
                    PACKET (w/pass-all packets)

Analysis Tools:     Third shift Cyrillic alphabet can be printed
                    on-screen.   Literal mode printing of data
                    received, databit mode, auto baudrate, tuning and shift
                    determination.  Start printer when upto 3 matching
                    selcalls are received.  On-screen tuning scope.
                    Screen print and screen saver.  Multi-channel ARQ
                    surveillance function.  Signal spectrum display.
                    User settable signal filters.  Multiple scroll
                    inhibit and Unshift on Space.  Built-in self test
                    functions.  Display has on-screen tuning bars and
                    real-time clock.

Extras Required:    VGA colour monitor (640x860 resolution or better)
                    Graphics compatible parallel printer (for FAX)

Supplier:           (US) Universal Radio, 6830 Americana Parkway,
                    Reynoldsburg, Ohio, OH 43068, USA  Tel: 614 866 4267
                    (UK) Martin Lynch, 140-142 Northfield Avenue,
                    Ealing, London, W13 9SB, United Kingdom
                    Tel: +44 181 566 1120

6-B HOBBIEST UNITS                                               HOBBIEST UNITS
UNIT NAME          |M|L|SYNOPSIS                            |MODES                    
Momentum Communi-  |1|E|A self-contained decoder,requires a |Baudot RTTY:45.45
 cations MCL 1100  | | |composite monitor for display. On-  |50,75,100,110,200
 "Easy Reader"     | | |screen tuning graph is displayed w/ |300bd, ASCII:45.45
                   | | |status line. Auto or manual tuning  |50,75,100,110,200
                   | | |of signal supported. Optional serial|300bd. SITOR-A/B,
                   | | |port supported. 12V DC power supply |CW
                   | | |needed.                             |
ERA Microreader Mk2|2|E|A self-contained decoder w/16 char  |Baudot RTTY:45.45
 version 4.2       | | |LCD display of incoming text,decodes|50,75,100bd, 
                   | | |all basic HF modes and includes a   |SITOR-A/B, CW
                   | | |Morse tutor. Serial port allows text|
                   | | |to PC. 12V DC power supply needed.  |
                   | | |LED tuning bar graph supported.     |
Lowe Mode Master V2|3|E|Easy to use software-based decoder  |Baudot RTTY, CW,
                   | | |from the makers of the popular HF-  |SITOR-A, SITOR-B,
                   | | |series receivers.  The system de-   |FAX
                   | | |codes the basic HF systems and also |
                   | | |provides a map facility for driving |
                   | | |the system. IBM PC needed.          |
Lowe AirMaster V3.0|3|E|Easy to use software-based decoder  |ACARS
                   | | |dedicated to the decoding of ACARS  |
                   | | |aircraft reporting system. The de-  |
                   | | |coder consists of a small hardware  |
                   | | |interface that connects to a free   |
                   | | |serial port on an IBM compatible PC.| 
                   | | |PC is required.                     |
PC/SWL [8/90pc]    |6| |This low cost unid used DSP in      |CW (3 to 100wpm)
                   | | |hardware. Need 286 or better, 384K  |Baudot (45 to 100)
                   | | |memory, 1 serial port. Supports     |Ascii (75 to 300)
                   | | |tuning and digital scopes, auto-    |SITOR A and B
                   | | |signal ID, tunable filters and      |Navtex
                   | | |variable shifts, unattended capture |
                   | | |and printing.                       |
                   | | |                                    |
HAL P38            |8| |The only game in town for afford-   |CLOVER
                   | | |able Clover processing. This plug-in|PACTOR,AMTOR,
                   | | |DSP card works on 386/486 based DOS |BAUDOT,ASCII
                   | | |computers. It offers programmable   |
                   | | |tones for AMTOR, PACTOR and RTTY and|
                   | | |supports all CLOVER modulation      |
                   | | |formats.                            |
                   | | |                                    |
Franklin Converter |9| |PC based software and external      |SSTV 15 modes
  [10/95mt]        | | |converter can receive, store and    |RTTY,CW,ASCII,
                   | | |process FAX. Supports common amateur|NAVTEX,AMTOR
                   | | |modes. Audio spectrum analyzer and  |
                   | | |tuning scope supported.             |
                   | | |                                    |
KAM+ Multi-Mode    |A| |Stand-alone unit supports all       |AMTOR,RTTY,ASCII,
  Controller       | | |amateur modes and is the ONLY unit  |GTOR,PACTOR,CW,
                   | | |that support GTOR. Dual port        |HF&VHF PACKET,
                   | | |operation supported. Programmable   |NAVTEX,WEFAX
                   | | |Mark/Space supported.               |support available
                   | | |                                    |
                   | | |                                    |
                   | | |                                    |
                   | | |                                    |
MFJ462B stand-alone|B| |Includes printer port, 8k message   |RTTY,CW,SITOR-B,
 reader            | | |memory, tuning indicator, CW speed  |ASCII
                   | | |tracking. Printer expects Epson     |
                   | | |compatibility                       |
MFJ1214PC          |B| |Tuning indicator for RTTY, CW speed |RTTY,CW,ASCII,
                   | | |tracking, WeFAX can show 16 grey    |WeFAX and color
                   | | |levels or full color. FAX requires  |FAX
                   | | |512k RAM and can zoom. VGA is       |
                   | | |supported.                          |
MFJ1278B           |B| |Fax/SSTV supports 16 grey levels and|RTTY,PACKET,FAX,
                   | | |color. SSTV supports Robot color    |PACTOR,SITOR-A/B,
                   | | |36/72, Robot B/W 8/12/24/36, Scotty |SSTV
                   | | |color 1/2, Martin color 1/2 and AVT |
                   | | |90/94. VIS tones are supported.     |
                   | | |Signals analysis supported on RTTY, |
                   | | |ASCII,PACKET,SITOR-A/B. 20 LED      |
                   | | |tuning indicator included.          |
                   | | |                                    |
                   | | |Options: MFJ1278/DSP - DSP installed|
                   | | |         MFJ1278BT - 2400bd packet  |
                   | | |                     mode built in  |
BMK-MULTY v3.43    |C| |Versatile unit supports the amateur |RTTY,CW,AMTOR,
                   | | |modes. Audio signal analyzer (opt)  |PACTOR (opt), FAX
                   | | |and logging are supported. Supports |and SSTV (opt)
                   | | |transmit on all modes. Supports a   |
                   | | |variety of interfaces: ST5/6,AEA-CP1|
                   | | |BARTG MULTYTERM,G3LIV PC internal   |
                   | | |modem,G3IQI modem. Low cost options |
                   | | |(20.00) and upgrades (5-10.00)      |
                   | | |                                    |
Personal Code      |D| |Hardware card supports the common   |CW, RTTY, FAX,
 Explorer          | | |modes with good FAX performance.    |SITOR-A/B, PACKET
   [4/93mt]        | | |Needs a CPU w/greater then 8MHz     |ASCII, Navtex
                   | | |speed, 512K memory, 1 serial port.  |
                   | | |Includes tuning scope and will store|
                   | | |FAX but not RTTY output.            |
                   | | |                                    |

(1) Momentum Communications, 6-7 Clarkson Place, Dudley
    Road, Lye, West Midlands, DY9 8EL, United Kingdom Tel: +44 1384 896879
(2) ERA, 26 Clarendon Court, Winwick Quay, Warrington,
    WA2 8QP, United Kingdom Tel: +44 1925 573118
(3) Lowe Electronics, Chesterfield Road, Matlock,
    Derbyshire, DE4 5LE, United Kingdom. Tel: +44 1629 580800
(6) Software Systems Consulting, 615 S. El Camino Real
    San Clemente, CA 92672 Tel: (714) 498-5784
(8) HAL Communications Corp, P.O. Box 365, 
    Urbana, IL 61801-0365 Tel: (217) 367-7373
(9) Logic Limited, 113 Cascade St., Morganton, NC  28655
    Tel: orders (800) 439-8898 tech line (704) 437-1833
(A) Kantronics
(B) MFJ, Box 494, Miss. State, MS 39762
    Tel: orders (800) 647-1800 tech line (800) 647-TECH(8324)
(C) written by G4BMK
    Spheretron/Schnedler Systems/AC4IW - distributer
    25 Eastwood Rd., P.O. Box 5964, Asheville, NC. 28813 Tel: (704) 274-4646
(D) Microcraft Corporation, Box 513M, Thiensville, WI 53092
    Tel: (414) 241-8144

UNIT NAME          |M|L|SYNOPSIS                            |MODES                    
Hamcomm (Version 3)|1|I|This PC-based decoder is trialware. |Baudot RTTY:45-
                   | | |The interface, which connects to the|200bd, CW 5-40wpm,
                   | | |PC serial port, can be built at     |SITOR-A/B, ASCII
                   | | |little cost. Despite being low-cost |
                   | | |the decoder is a fine piece of soft-|Signal Osciloscope
                   | | |ware w/features found in decoders   |Spectrum Analyser
                   | | |costing over $100. PC, monitor and  |Bit Len. Analyser
                   | | |1 serial port needed.               |Tuning Aid + Meteo
                   | | |                                    |SYNOP,SHIP and WX
                   | | |30 days free. registration: US$30   |decoder.
JVFAX 7.0          |2|I|JvFax is a shareware program for the|FAX IOC 200-576
                   | | |reception of wx and photo style fax.| LPM 48,60,90,120,
                   | | |It also includes a transmit option  | 180,240,360,480
                   | | |for Fax and an SSTV transmit and    |SSTV B/W 8,12,24s
                   | | |receive mode. Reception can be auto-| Scottie S1/S2/DX
                   | | |mated and features time scheduling. | Martin M1/M2
                   | | |Automatic creation of wx movies is  | Wraase 24,48,96
                   | | |supported when receiving from geo-  |
                   | | |stationary sat. GIF format is used  |
                   | | |to store pictures, but 24 bit un-   |
                   | | |compressed TIF can be used.         |
                   | | |IBM PC w/DOS 3.0+4 MB of RAM needed.|
                   | | |WINDOWS or OS/2 is NOT SUPPORTED.   |
FTV 0.98f          |3|I|SoundBlaster based decoder of FAX,  |FAX, SSTV, RTTY
                   | | |SSTV modes and RTTY. Supports auto- |WEFAX
                   | | |mode recognition, sync lock and     |
                   | | |phasing. APT signal reception is    |
                   | | |supported. FM (HF FAX/SSTV mono and |
                   | | |color, AM (weather sat) supported.  |
                   | | |                                    |
                   | | |80386, soundblaster compatible, 256k|
                   | | |needed, 1024k preferred, SVGA w/VESA|
                   | | |(640x480, 256 color). Unregistered  |
                   | | |version disables saves.             |
RadioRaft 2.0      |4|I|A comparator based program. Supports|BAUDOT,ASCII,SITOR
                   | | |automatic decoding,speeds from 10 to|A/B,ARQ-E,ARQ-M2/4
                   | | |6400bps,bit display for analysis    |PACKET,ARQ-E3,
                   | | |(DIGIT). This allows setting word   |ROU-FEC,FEC-A,
                   | | |size,parity,sync/async,bin/hex and  |SI-ARQ,SWED-ARQ,
                   | | |character code options.             |ARQ6-90/98,CIS-11,
                   | | |                                    |SPREAD11/21/51,CW,
                   | | |                                    |AUTOSPEC,SI-FEC,
                   | | |                                    |ARQ-N,HNG-FEC
                   | | |                                    |
                   | | |386/486/Pentium,VGA,com port,650K   |
                   | | |disk,550K mem,runs in DOS. LITE     |
                   | | |version freely available, 28.00 for |
                   | | |registered version.                 |

(1) W. F. Schroeder, Augsburger Weg 63, D-33102 Paderborn, Germany

    Also on many BBSes and Internet Archives.
    Hamcom approx. price: Registration Fee of USD30 or DM40

(2) Trialware
(3) Brian E. Cauchi, 9H1JS
(4) Francois Guillett, F6FLT

6-D. VHF SPECIFIC UNITS                                   VHF SPECIFIC UNITS
UNIT NAME          |M|L|SYNOPSIS                            |MODES                    
MessageTracker v2.0|1| |Software displays and stores pager  |Golay
                   | | |messages. Auto polarity and baud    |POCSAG all speeds
                   | | |rate detection supported. Can handle|
                   | | |golay and multispeed pocsag on the  |
                   | | |same freq.                          |
Pager Datascope    |2| |Software is designed to diagnose    |POCSAG all speeds
                   | | |pager hardware, software, and wire- |
                   | | |less media. Alpha and numeric trans-|
                   | | |lation is displayed and written to  |
                   | | |disk. Can display and store synch-  |
                   | | |ronous bit patterns. tune indicator |
                   | | |on screen. Display of CAP code, date|
                   | | |time stamp and info plus results of |
                   | | |error correction supported.         |
ACT1 ACARS         |4| |ACARS decoding software and hard-   |ACARS
                   | | |ware. Uses 1 serial port on IBM     |
                   | | |computer. Supports view, print,     |
                   | | |save of text traffic. Requires 8088 |
                   | | |CPU or better, 1 25 pin serial port.|
PD2.03             |5| |A trialware package designed to     |POCSAG all speeds
                   | | |decode POCSAG paging signals at 512,|
                   | | |1200 and 2400bps. Decoding of alpha-|
                   | | |numeric and numeric pager data is   |
                   | | |supported. Includes hex dump of raw |
                   | | |data.                               |
                   | | |                                    |
                   | | |Requires PC running DOS w/1 serial  |
                   | | |port. Windows not supported.        |
KRACARS v1.2       |6| |A Freeware package that uses a      |ACARS
                   | | |SoundBlaster Pro or SoundBlaster 16 |
                   | | |to decode acars in real-time.       |
                   | | |                                    |
                   | | |Requires PC w/DOS w/SB soundcard    |
                   | | |Can run in Win95 DOS box            |
WACARS v0.1        |7| |A Freeware package that uses a PC   |ACARS
                   | | |soundcard to decode acars.          |
                   | | |                                    |
                   | | |Requires Win3.1 or better w/at least|
                   | | |150MHz CPU and Soundcard capable of |
                   | | |recording at 19.2Kbs. This is non-  |
                   | | |standard but works w/SoundBlaster 16|

(1) K&L Technology, P.O. Box 460838, Garland, TX  75046-0838
    Tel: (214) 414-7198 Email: 
(2) JSoft Technologies: via Universal Radio, 6830 Americana Parkway,
    Reynoldsburg, Ohio, OH 43068, USA  Tel: 614 866 4267
(4) Universal Radio, 6830 Americana Pkwy, Reynoldsburg, OH, 43068
    Tel: (800) 431-3939/(614) 866-4267
(5) Peter Baston, 7 Allerton Close, Pen-y-fford, Chester, CH4 0NL, UK
    20.00 Pounds Sterling
(6) Khalid Rafiq,

Section 7. Reference Materials

The following are a series of references related specifically to Utility
Monitoring. They cover logs, technical information on signals, World Wide Web
pages and signal sources. You can never have enough references when it comes
to Digital Utilities.

7-A. WWW Resources

  Equipment Manufacturers Web Pages and E-mail
* Hoka (UK): e-mail:

  Computer Aided Technologies/Hoka (US-rep): e-mail:

  Wavecom:   e-mail:

  Universal: e-mail:

* HAL:       e-mail:

  LOWE:      e-mail:

  Kantronics: e-mail:

  JSoft:     e-mail:

  K&L Tech.  e-mail:
             http: none

  Publishers - Documents, Magazines and Databases

  Klingenfuss Publications: 


  Monitoring Times:

             e-mail: (Marius Rensen)

  Mailing lists
  WUN        Dedicated mailing list sponsored by the Worldwide Utility
             News Club. Topics cover full range of utility related
             material. Monthly newsletter. Logs welcome.

             Subscription Policy: OPEN
             contact point:

  code3list  a mailing list dedicated to Hoka Code 3 and Code 3 Gold
             decoder. Not manufacturer sponsored. Topics include use,
             hints, tips, problems, etc.

             Subscription Policy: OPEN
             contact point: (Stan Scalsky)

  code30users a mailing list dedicated to the Hoka Code 30 decoder. 
              Not manufacturer sponsored. Topics included use, tips,
              problems and issues related to analysis.

              Subscription Policy: CLOSED
              contact point: (Stan Scalsky)

   acars      a mailing list dedicated to ACARS monitoring. All decoders
              covered, logs welcome. 

              Subscription Policy: OPEN
              contact point: (Mike Agner)
7-B. Magazines and Books

WUN/Worldwide Utility News Club - a worldwide electronic club dealing 
       exclusively with Utility Signals on HF. Newsletter is sent on a 
       monthly basis electronically. Topics covered include International 
       Civil Aero, Logs, Digital Signals, Nautical, Military, Numbers and 
       Longwave. For further info see
       To subscribe send mail to:

          In the BODY of the message type: 
          subscribe wun. 

International Telecommunication Union
       The ITU publishes lots of information, all avaiable at cost, on all
       aspects of radio and its management. One of the best and most 
       applicable documents the ITU makes available is:

            Spectrum Monitoring Handbook 1995 (ISBN: 92-61-05761-6)

        International Telecommunication Union
        Sales and Marketing Service
        Place des Nations
        CH - 1211 Geneva 20

Monitoring Times - An all round, covers all aspects of the shortwave hobby 
       type of magazine.  No regular RTTY column since Jack Albert stopped 
       writing but covers some digital issues in their Federal File, 
       Utility World or Digital Digest columns. This magazine is published
       by Grove Enterprises.

          Monitoring Times
          P.O. Box 98
          300 S. Highway 64 West
          Brasstown, NC  28902-0098

          $23.95/yr - U.S.  
          $34.00/yr - U.S. funds elsewhere

RTTY Listener - This newsletter "was" available free of charge to owners of
       Universal decoder boxes (M1000, M1200, M7000 and M8000). Bound reprints
       are available from Universal. Last issue was published Dec '94 with a 
       followup issue published in Apr '97. The reprints are good references
       if you own any of the Universal line of decoders.

          Universal Radio
          6830 Americana Pkwy.
          Reynoldsburg, OH  43068

Klingenfuss - Well known publisher of frequency reference guides.  Their 
       publications can be found at many radio/Ham equipment suppliers. The 
       references tend to be Eurocentric but are non the less valuable and 

       The Radio Data Code Manual (combined Radioteletype Code Manual and Air
       and Meteo Code Manual) is especially valuable for those that want some
       of the bit-level information about the various protocols found on the 
       shortwave spectrum. A unique reference book for the digital monitor.

          Klingenfuss Publications
          Hagenloher Str. 14
          D-72070 Tuebingen

          From the Jan'97 catalog:
            1997 Guide to Utility Stations [15th edition]    DEM 80
            1996/1997 Guide to Worldwide WeatherFax Services DEM 60
            Radio Data Code Manual [15th edition]            DEM 70

Ferrell's - Confidential Frequency List - 10th Edition.  A solid reference 
       covering a wide range of signal types - Aero, Marine, Fixed, Embassy,
       Military, Fax. Frequencies collected from a wide variety of sources:
       individuals, clubs, journals and official sources. Published by PW
       Publishing and compiled by Geoff Halligey.

Siebel Verlag - A good solid reference, published every 2 years with good 
       coverage of digital modes. While the text is written in German the 
       frequency log are all easy to read. Check out WUN V2.3 March '96 for 
       a complete review. 

          9kHz - 30MHz
          Ausgabe 1996/1997
          By Rainer Brannolte/Wolf Siebel
          ISBN: 3-922221-80-7
          Price: 34.80 DM

          Siebel Verlag
          Auf dem Steinbuechel 6
          D-53340 Meckenheim
          Tel: ++49-2225-3032
          Fax: ++49-2225-3378

7-C. Frequency Databases

       1997 Super Frequency List [3rd edition]           DEM  60

          Klingenfuss Publications
          Hagenloher Str. 14
          D-72070 Tuebingen

    Frequency Manager for Shortwave Listener

Ingenieurburo fur Satellitentechnik

        23000 up-to-date frequencies and 10000 callsigns for aero, coast,
        fixed, embassy, fax, volmet and military. More than 150 pages,
        descriptions, tables, all HF-systems as a technical handbook
        integrated in a special help system. Tables on NATO routing
        indicators, routing indicators for AFTN, callsigns, arabic
        translations, HF-systems, table of system parameters with users,
        recognizing PSK and formats of common telegramms

        PC-Frequenz            US 60
        Broadcast module (optional)    US 20
        Quarterly update        US 20

            Ingenieurburo fur Satellitentechnik
            Muhlenweg 11
            24217 Stakendorf
            Tel: 01149 4344 6758
            Fax: 01149 4344 5154

SHOC RadioData
       SHOC has a Utility database that covers many services such as DIPLO 
       stations, Air, Maritime, Military, Police, Government, Disaster relief,
       United Nations, Defense, ICRC/Read Cross, Press Agencies, Telecom, FAX,
       Meteo and Time Signals.  The database is maintained by professionals in
       the monitoring business and is continuously updated. The database 
       includes info such as: frequency, station, callsign, mode, baudrate, 
       shift, latitude and longitude of the transmitter. See their homepage for
       a complete list of supported database fields and information on the 
       other databases and products they offer.

       RadioData Utility Database  300.00 SFr.

          Mail/FAX to:

          Weiherhof 10
          CH-8604 Volketswil
          Tel: +41-1-997 15 55  FAX: +41-1-997 15 56

7-D. Tape and CD Reference Materials

Klingenfuss -    A unique way to test your decoder is to use one of the
       following audio reference materials. These sources allow you to 
       hear and decode what the various modes sound like.

       Compact Cassette Recording of Modulation Types [6th edition]  DEM 60
       Compact Disc Recording of Modulation Types [1st edition]      DEM 100

          Klingenfuss Publications
          Hagenloher Str. 14
          D-72070 Tuebingen

Siebel Verlag - A demonstration cassette is also available from the makers of
       the Spezial-Frequenzliste. The cassette includes a selection of commonly
       found signals: Baudot - various bauds and shifts, Sitor-A/B, ARQ-E, 
       FAX and CW. Available from the address above. Price: 19.80 DM

Section 8. Appendix

8-A. Appendix A - Abbreviations

The use of abbreviations is becoming quite common and sometimes confusing
in todays radio related literature. There has been an explosion of new
DSP related technology in recent years being applied to all aspects of
telecommunications. Below is a modest attempt to define some of the more 
frequent abbreviations as found in the radio monitoring literature. Trying
to explain the theory behind many of these abbreviations would fill several
sizeable textbooks so I will not attempt in depth explanations. A list of
abbreviates can be lengthy so I have attempted to limit the list to those
directly related to topics of modulation and analysis. Additions welcome.

Abbreviations designating Modulations
AFSK         Audio Frequency Shift Keying
APSK         Amplitude Phase Shift Keying
ASK          Amplitude Shift Keying
BPSK         Binary Phase Shift Keying
CPFSK        Continuous Phase FSK
DPSK         Differential Phase Shift Keying
FEK          Frequency Exchange Keying
FFSK         Fast Frequency Shift Keying (also called MSK)
FSK          Frequency Shift Keying
GFSK         Wavecom term
MFSK         Multi Frequency Shift Keying
MSK          Minimum Shift Keying
OOK          On/Off Keying 
OQPSK        Offset Quad Phase Shift Keying
PCM          Pulse Code Modulation
PSK          Phase Shift Keying
QAM          Quad Phase Shift Keying with Amplitude Modulation
             Quadrature Amplitude Modulation
QPSK         Quad Phase Shift Keying

2DPSK BPSK   2-phase Differential Phase Shift Keying
4DPSK QPSK   4-phase Differential Phase Shift Keying
BPSM         Binary Phase Shift Modulation
QPSM         Quadrature Phase Shift Modulation
8PSM         8-level PSM
8P2A         8PSM + 2-level ASM
16P4A        16PSM + 4-level ASM
8PSK         8-phase states 0/45/90/135/180/225/270/315, each phase change
16PSK        16-phase states or 22.5 degrees per phase, each phase change
8P2A         ASK with 8PSK
16P4A        ASK with 16PSK

Abbreviations generally related to Radio and Analysis 
ACF          Auto Correlation Function
ARQ          Automatic Request for Repeat
DFT          Discrete Fourier Transform
DSB          Double Side Band
FDM          Frequency Domain Multiplex
FEC          Forward Error Correction
FFT          Fast Fourier Transform
ISB          Independent Side Band
LSB          Lower Side Band
SSB          Single Side Band
TDM          Time Domain Multiplex
USB          Upper Side Band
VFT          Voice Frequency Telegraphy

8-B. Appendix B - Emmission Classification

Quite frequently emmission designators appear in logs from various sources
including WUN logs. Not everyone, especially if you are not into amateur
radio, is familiar with the meaning of the more commonly used classes
such as F1B, F7B or B9W. 

Article 4, Section II, of the Radio Regulations, Geneva, 1986 defines the
following symbols for the purpose of classifing emissions. The classification
system is used by official monitoring stations in coordinating monitoring 
efforts. The correct classification of received emissions is also used to 
resolve and develop interference techniques and for station identification.

For the complete description of an emission, the bandwidth (in 4 characters)
is added in front of the classification. See the examples section.

      +------------------------ type of modulation on the carrier
      | +---------------------- nature of signal on main carrier
      | | +-------------------- type of information
      | | | +------------------ detail of signals
      | | | | +---------------- kind of multiplexing
      | | | | | +-------------- Group of system
      | | | | | | +------------ System in Group
      | | | | | | |

 aaaa X X X Y Y Z Z
                                      123 - required
      1 2 3 4 5 6 7                   45  - optional
      +---+ +-+ +-+                   67  - supplement
a) No modulation        ----------> N  unmodulated
b) Amplitude modulation ----------> A  DSB, double sideband
c) Angle modulation     --------+   H  SSB, single sideband full carrier
d) (b)+(c) combo or seq ------+ |   R  SSB, single sideband variable carrier
e) Pulse                ----+ | |   J  SSB, single sideband suppressed carrier
f) None of the above    --+ | | |   B  ISB independant sideband
g) Everything else      + | | | |   C  vestigial sideband
                        | | | | |
                        | | | | +-> F  FM, frequency modulation
+------------+          | | | |     G  Phase modulation
| 1st symbol |          | | | |
+------------+          | | | +---> D  combo
                        | | |
                        | | +-----> P  unmodulated sequence of pulses
                        | |         K  amplitude modulation
                        | |         L  width or duration is modulated
                        | |         M  position or phase is modulated
                        | |         Q  angle modulated during pulse
                        | |         V  pulse - other
                        | |
                        | +-------> W  emission - other
                        +---------> X 

                      0   No modulating signal
                      1   single channel/digital info/no modulating sub-carrier
+------------+        2   single channel/digital info/modulating sub-carrier
| 2nd symbol |        3   single channel analog info 
+------------+        7   2 or more channels digital info
                      8   2 or more channels analog info
                      9   composite system
                      X   other

                      N   No information
                      A   Telegraphy - aural reception
                      B   Telegraphy - automatic reception
+------------+        C   Fax
| 3rd symbol |        D   Data or telemetry
+------------+        E   Telephone
                      F   Television
                      W   Combo of above
                      X   None of the above

Appendix 6, part A  of the Radio Regulation, Geneva, 1986 allows for two
other classifications. If neither symbol is available then a - should
appear in their place.

                      A   binary - elements of differing numbers/duration
                      B   binary - elements with same number and duration,
                          no error correction
                      C   binary - elements with same number and duration,
                          error correction
                      D   4-ary  - each condition equals 1 signal element
                      E   multi  - each condition equals 1 signal element
+------------+        F   multi  - each condition or combo equals 1 character
| 4th symbol |        G   sound of broadcasting quality - monophonic
+------------+        H   sound of broadcasting quality - stero or quadrophonic
                      J   sound of commercial quality
                      K   sound of commercial quality w/frequency inversion 
                          or band-splitting
                      L   sound of commercial quality w/separate FM signals 
                          to control demod level
                      M   monochrome
                      N   color
                      W   combo of above
                      X   none of the above

                      N   none
                      C   code-division multiplexing
+------------+        F   frequency-division multiplexing
| 5th symbol |        T   time-division multiplexing
+------------+        W   combined frequency-division and time-division 
                      X   other

Supplementary information is not required but is usually helpful for a 
complete identification. The following table lists the currently known
supplements as defined by the ITU. The table uses further qualifiers as
listed below:

In the case of multitone systems further qualification will be found showing
duration of each tone, tone shift and number of tones. For example:

    TT2300b: 010/200/008 - 10ms tone duration
                         - 200Hz shift between tones
                         - 8 tones present in the signal

For multichannel systems a similiar arrangement is used but will show
shift in channel, channel spacing, number of channels. For example:

    BR6028: 170/340/007 - 170Hz channel shift
                        - 340Hz channel spacing
                        - 7 channels in the signal

6th symbol - Group of system
                      A   Morse
                      C   Asynchronous
                      E   ARQ
                      F   ARQ burst type
                      H   TWINPLEX
                      J   Unknown
                      K   FEC
                      M   Multitone
                      N   Radionavigation and location

7th symbol - actual system in group 

 A- Morse                            H- TWINPLEX
                                     HA SITOR F7B-?
 C- Asynchronous                     HB       F7B-1
 CB telex Baudot                     HC       F7B-2
 CC telex Russian                    HD       F7B-3
 CD telex Arabic                     HE       F7B-4
 CK telex ASCII                      HF       F7B-5
                                     HG       F7B-6
 E- ARQ pulse train                  HH with ASCII
 EA ARQ-1000 duplex                  HK with Baudot
 EB ARQ-E3                           HL F7 Baudot/Morse
 EC 342 TOR 1 kan                    HM F7
 ED 342 TOR 2 kan
 EE 342 TOR 4 kan                    J- Unknown
 EF 242 TOR 2 kan                    JA ARTRAC
 EL POL-ARQ                          K- Forward Error Correction
 EM TORG 10-11                       KA FEC-100
                                     KB SITOR-B
 F- ARQ (burst)                      KC FEC1000 Simplex
 FA Simplex/SITOR                    KD Autospec
 FB                                  KE ROU-FEC
 FC ARQ 1000 Simplex                 KF HNG-FEC
 FE ARQ6-70                          M- Multitone
 FF ARQ6-90                          MA Piccolo MK6 w/ITA2
 FG ARQ6-98                          MB Piccolo MK6 w/ITA5
 FH UN-ARQ                           MC Piccolo MK1/330
 FI HC-ARQ                           MF Rus. Piccolo 1  025/040/034
 FK RS-ARQ                           MG Rus. Piccolo 2  025/010/034
 FL ARTRAC                           MH Rus. Piccolo 3  100/040/034
 FN PACKET                           MI Rus. Piccolo 4  100/010/034
 FX P 162                            ML Coquelet MK1
                                     MM Coquelet MK1
                                     MP TT2300b


N0N                    Unmodulated carrier
A1A                    CW telegraphy, standard Morse alphabet, no sub-carrier
A2A                    CW telegraphy, standard Morse alphabet, with sub-carrier
A3E                    DSB, used by broadcasting stations
B7B                    VFT on LSB, VFT on USB
B8E                    ISB, often used by broadcasting stations (feeders)
B9W                    voice on LSB, VFT on USB
F1A                    Telegraphy, Cyrillic Morse alphabet
F1B, F7B               RTTY
F1C, F2C, F3C          FAX, FM
J2C, J3C               FAX, AM
J3E                    SSB, telephony, suppressed carrier
R3C                    FAX

CLOVER                 500HJ2DEN
SITOR-A                F1BCN FA
BAUDOT                 F1BBN CB
TWINPLEX F7B-2         F7BDX HB 175/200/175

         .-.                                                         .-.
        /   \           .-.                           .-.           /   \
       /     \         /   \       .-.     .-.       /   \         /     \
      /_The END_______/The END____/___\___/___\_____/The END______/_The END
               \     /       \   /     `-'     \   /       \     /
                \   /         `-'               `-'         \   /
                 `-'                                         `-'

copy of original archive can be retrieved by pages