Small TX spike

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Small TX spike

Post by VE3TMT »

I'm noticing a little TX spur just above my TX signal in WSJT-X. I've tried lowering the TX GAIN and the drive level with no success.


SDRScreenSave__DIGU_7.074000MHz_11-12-2022 6_58_42 PM.jpg
SDRScreenSave__DIGU_7.074000MHz_11-12-2022 6_58_42 PM.jpg (93.91 KiB) Viewed 13578 times
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Re: Small TX spike

Post by ke9ns »

From the photo the harmonic is over 60db down so your good
Enable the 2nd TX meter for COMBO, and make sure the MIC and ALC stay at or below 0db when you hit TUNE in WSJT-X (not PowerSDR TUN)
Make sure your VAC1 sample rate matches the sample rate of the virtual cable your using (I use 44100 with VB-Cable).

Creator of PowerSDR KE9NS v2.8, based on the Flex Radio PowerSDR v2.7.2 software.
Flex-5000, LDMOS and Titan Amps, G5RV, and Mosley TA-33 Junior
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Re: Small TX spike

Post by w5ktw »

Try going to DSP and setting the sample rate for TX to 2048. Cleaned my signal up
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