Ciao, ho scaricato un pacchetto per Ubuntu: multimon.
QUesto programma consente di operare per il coded/decoder di segnali audio con l'ausilio della scheda audio.
(da terminale con: man multimo non ho trovato grandi informazioni) Ma è possibile questa cosa? O mi sbaglio io?

Ecco qua il manuale di questo programma: che cosa fa realmente e a che serve?


MULTIMON(1) MUL
TIMON(1)

NAME
multimon - program to decode radio transmissions

SYNOPSIS
multimon [options] [input_file]

DESCRIPTION
This manual page documents briefly the multimon command. Thi
s manual
page was written for the Debian GNU/Linux distribution beca
use the
original program does not have a manual page.

The multimon software can decode a variety of digital tran
smission

modes commonly found on UHF radio. A standard PC soundcard is
used to
acquire the signal from a transceiver. The decoding is done co
mpletely
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 t
he 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 som
e 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 t
elephone
dialing.
ZVEI- The German Electrical and Electronic Manufacturers’ Assoc
iation -
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 m
aud vwe

-a <demod>
add demodulator

-s <demod>
subtract demodulator

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 spe
cify 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 t
he sound
card using the /dev/dsp interface. So to decode (only) DTMF t
ones 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)

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

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

June 19, 2000 MULTIMON(1)