NAME

       multimon - program to decode radio transmissions

SYNOPSIS

       multimon [options] [input_file]

DESCRIPTION

       This manual page documents briefly the multimon command.  This manual page was written for
       the Debian GNU/Linux distribution because the original program  does  not  have  a  manual
       page.

       The multimon software can decode a variety of digital transmission modes commonly found on
       UHF radio. A standard PC soundcard is used to acquire the signal from a  transceiver.  The
       decoding is done completely in software. Currently, the following modes are supported:

           * AX.25
                        o 1200 Baud AFSK
                        o 2400 Baud AFSK (2 variants)
                        o 4800 Baud HAPN
                        o 9600 Baud FSK (G3RUH)

           * POCSAG
                        o 512 Baud
                        o 1200 Baud
                        o 2400 Baud

           * Miscellaneous
                        o DTMF
                        o ZVEI
                        o SCOPE

       An  arbitrary  set  of  the  above  modes  may  run  concurrently on the same input signal
       (provided the CPU power is sufficient), so you do not have to know in advance  which  mode
       is used. Note however that some modes might require modifications to the radio (especially
       the 9600 baud FSK and the POCSAG modes) to work properly.

       AX.25 - Amateur Packet Radio protocol datagram format
       POCSAG (Post Office Code Standards Advisory Group) is a common paging transmission format.
       DTMF - Dual Tone Multi Frequency. Commonly used in in-band telephone dialing.
       ZVEI- The German Electrical  and  Electronic  Manufacturers'  Association  -  paging  tone
       format.
       SCOPE - show samples in a rudimentary oscilloscope display on an X server.

       Multimon does not decode Morse code signals.

OPTIONS

       -t <type>
              input file type (any other type than raw requires sox)
              allowed types: raw aiff au hcom sf voc cdr dat smp wav maud vwe

       -a <demod>
              add demodulator

       -s <demod>
              subtract demodulator

       -v <num>
              verbosity level (0-10)

       -q     quiet output messages

       Where  <demod> is one of: POCSAG512 POCSAG1200 POCSAG2400 EAS AFSK1200 AFSK2400 AFSK2400_2
       HAPN4800 FSK9600 DTMF ZVEI SCOPE
       The -a and -s options may  be  given  multiple  times  to  specify  the  desired  list  of
       demodulators.

EXAMPLE

       Decode  signal  modulations  from  a  sound  file  /tmp/message.wav  without using a SCOPE
       display:
       multimon -s SCOPE -t wav /tmp/message.wav

       With no input file specified, the program listens directly to the  sound  card  using  the
       /dev/dsp interface.  So to decode (only) DTMF tones on the sound card input:
       multimon -a DTMF

NOTICE

       Please  note that monitoring commercial services may be prohibited in some countries, this
       software should therefore only be used to monitor the amateur radio service.

SEE ALSO

       gen(1)                                       http://www.qsl.net/kb9mwr/projects/pager/Two-
       Tone%20Pager%20Decoding%20Using%20Multimon.pdf

BUGS

       The DTMF and ZVEI decoders have more frequent spurious detection reports.

AUTHOR

       This  manual  page was written by A. Maitland Bottoms <bottoms@debian.org>, for the Debian
       GNU/Linux system (but may be used by others).

                                          June 19, 2000                               MULTIMON(1)