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Posted by Matt KC8COM [ burnsmatt324@gmail.com ] on November 04, 2026 at 00:46:36.
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Hi, I have recently developed and tested a computer program to send QRSS voice. The program works by slowing a short recorded message by 5, 10, 20, 50, 100, or 200 times then upconverting the slowed speech by 1 KHz to put the slowed speech within the passband of an SSB transceiver. The receive section of the program includes a long running low bitrate, bandpassed recorder and will downconvert the recorded audio and restore it to normal speed. I have also included a program to correct linear frequency drift. An initial test on 15 meters at 1/100 speed showed a significant improvement in SNR to the ID given at regular speed and showed a 500 Hz linear drift (5 Hz actual drift, multiplied by the 100x speed increase) and was easily corrected. The transmission of a 5 second voice clip lasted 8 minutes and had a theoretical bandwidth of 23 Hz.((2400Hz-100Hz)/100). I think this would be an interesting mode for low power part 15 experimentation as well as QRPp on the ham bands. I have included a provision for an automatic cw id at the end of each transmission as well as one every 9 minutes for long transmissions. If anyone is interested in trying it out, please let me know either here or via email and I will post or send a link to the program and source code. 73 and thanks, Matt Burns
KC8COM
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