[MilCom] Axe Mill on the orderwire

pdgls via MilCom milcom at mailman.qth.net
Mon Mar 2 01:44:40 EST 2015


Been experimenting for a month now tuning WBFM subcarriers in the audio after WFM demodulation instead of tuning them in the WBFM RF signal using LSB.
WBFM freqs i scan are 286.1, 301.65, 338.95, 362.250 and 337.3 in WFM mode. 
A voice recorder is conected to the IC-R20 and recordings made in the highest sample rate possible.
Been trying two recorders, one records at 128 kbps and the other 192 kbps.
Audio file is then converted to 96 kbps 16 bit stereo wave file and played back in SDRSharp with its sample rate set to 192 kbps.
I usually use the RAW setting with the bandwidth set at 7000.
Since i'm getting the audio through the normal audio out and not a discriminator tap subcarriers in the ultrasound are not getting through.
The highest i've seen is the 16 Khz subcarrier so far.  
The 24 Khz, 32 Khz, 40 Khz, 48 Khz and 56 KHz subcarriers are probably filtered out in the IC-R20 and voice recorder audio circuits.  
The 8 Khz subcarrier is the only one i need to get the E-6B orderwire.
I don't know what subcarriers the E-4 and AF-1 use. They don't come around here very often.  
https://www.youtube.com/watch?v=7TQvKF0Gbxg

Paul, near Sacramento California


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