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ATEST(1) General Commands Manual ATEST(1)


atest - Decode AX.25 frames from an audio file.


atest [ options ] wav-file-in

wav-file-in is a WAV format audio file.


atest is a test application which decodes AX.25 frames from an audio recording. This provides an easy way to test Dire Wolf decoding performance much quicker than normal real-time.


Data rate in bits/sec. Standard values are 300, 1200, 2400, 4800, 9600.
300 bps defaults to AFSK tones of 1600 & 1800.

1200 bps uses AFSK tones of 1200 & 2200.

2400 bps uses QPSK based on V.26 standard.

4800 bps uses 8PSK based on V.27 standard.

9600 bps and up uses K9NG/G3RUH standard.

AIS for ship Automatic Identification System.

EAS for Emergency Alert System (EAS) Specific Area Message Encoding (SAME).

Force G3RUH modem regardless of data rate.

2400 bps QPSK compatible with Dire Wolf <= 1.5.

2400 bps QPSK compatible with MFJ-2400.

Divide audio sample rate by n.

Print frame contents as hexadecimal bytes.

Amount of effort to try fixing frames with an invalid CRC. 0 (default) = consider only correct frames. 1 = Try to fix only a single bit. more = Try modifying more bits to get a good CRC.

Error if Less than this number decoded.

Error if Greater than this number decoded.

Select the demodulator type such as D (default for 300 bps), E+ (default for 1200 bps), PQRS for 2400 bps, etc.


gen_packets -o test1.wav

atest test1.wav

gen_packets -B 300 -o test3.wav

atest -B 300 test3.wav

gen_packets -B 9600 -o test9.wav

atest -B 9600 test9.wav

This generates and decodes 3 test files with 1200, 300, and 9600 bits per second.

atest 02_Track_2.wav

atest -P E- 02_Track_2.wav

atest -F 1 02_Track_2.wav

atest -P E- -F 1 02_Track_2.wav

Try different combinations of options to compare decoding performance.


More detailed information is in the PDF files at

Applications in this package: aclients, atest, cm108, decode_aprs, direwolf, gen_packets, kissutil, ll2utm, log2gpx, text2tt, tt2text, utm2ll