RTTY Transmit Audio Sounds Awful in Monitor

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  • Updated 4 years ago
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I tried calling K5P on 40m RTTY this morning with MMTTY (latest version), SSDR 1.6.19 and FLEX-6700.

I now know how to set the TX / RX split in a RTTY pileup correctly however I noticed my TX audio sounds awful. I tried headphones, speaker (shielded powered studio monitor) and different DAX TX and monitor audio levels. Didn't make a difference.

My station is well grounded and the antennas are a 150 feet from the shack. I haven't had RFI issues on other modes.

What is causing the distortion in the monitor? Am I transmitting distorted as well (I had to leave for work before I could ask anyone to listen to my tx)?

I have a short video here: https://www.youtube.com/watch?v=FQkpoNqFPoc

Any help appreciated 

Bill AA7XT
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William Hein

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Posted 4 years ago

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Stu Phillips - K6TU, Elmer

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Official Response
Not clear which release you are using but I have experienced this intermittently in the past (not since using 1.6.17 BTW)...

The problem is likely due to a buffer corruption within the DAX driver.  Closing the DAX control panel (which closes all the DAX devices) and then restarting DAX (or a PC reboot) solves the problem.

You can often see the issue on the transmit waveform displayed on TX - it will be very broad and bot have the two clean peaks for the diddles.

Stu K6TU