SYNOPSISgen_packets -o wav-file-out [ options ] [ text-file | - ]
wav-file-out is the result. The -o option is required.
text-file may contain AX.25 packets in the standard monitoring format. Use "-" to read from stdin. If not specified, a default builtin message will be used.
DESCRIPTIONgen_packets is a test application which converts text to AX.25 audio for testing packet decoders.
It is very flexible allowing a wide range of audio sample rates, data speeds, and AFSK tones. It will even generate the scrambled signals commonly used for 9600 baud operation.
- -a n
Signal amplitude in range of 0-200%. Default 50. Note that 100% is corresponds to signal peaks of +/- 16383 so we have plenty of headroom to avoid saturation.
- -b n
Bits / second for data. Default is 1200.
- -B n
Bits / second for data. Proper modem selected for 300, 1200, 9600.
Scrambled baseband rather than AFSK.
- -m n
Mark frequency. Default is 1200.
- -s n
Space frequency. Default is 2200.
- -r n
Audio sample Rate. Default is 44100.
- -n n
Generate specified number of frames with increasing noise. (For built-in message only.)
- -o file
Send output to .wav file.
8 bit audio rather than 16.
2 channels of audio rather than 1.
gen_packets -o x.wav
- With all defaults, a built-in test message is generated with standard Bell 202 tones used for packet radio on ordinary VHF FM transceivers.
gen_packets -o x.wav -g -b 9600
gen_packets -o x.wav -B 9600
- Both of these are equivalent. "-B 9600" automatically selects scrambled baseband rather than AFSK.
gen_packets -o x.wav -m 1600 -s 1800 -b 300
gen_packets -o x.wav -B 300
- Both of these generate 200 Hz shift, 300 baud, suitable for HF SSB transceiver.
echo -n 'WB2OSZ>WORLD:Hello, world!' | gen_packets -a 25 -o x.wav -
- Read message from stdin and put quarter volume sound into the file x.wav. Decode the sound file.