Correcting Frequency Drift caused by dirty Offset Pot

Watching the PSK waterfall, the incoming signal drifts off and my software can,t decode it. Sometimes it comes back, sometimes I have to chase the signal. I don't know if it is doing the same on transmit. The frequency readout is not showing any change when this happens. The problem with the PSK reception seems to be limited to 20 meters. On a long winded ragchew with my slow typing, I have had a few people tell me that I drift a wee bit. On 10, 15, or 40 meters I am not having this trouble. (KM4FO)

When I had my Corsair 2, I had a warble on a number of the HF bands. I could clearly see it on PSK31 signals on the waterfall of MixW. I rebuilt the PTO a number of times but it didn't cure the problem.

Eventually it was traced to a dirty preset pot which set an offset voltage on those bands. I can't remember the component reference, but - if I remember right - it was the only one on the board and sat up at right angles to the board. A squirt of switch cleaner did the trick.

For you, this may be the cause of your problem. Anyway, if you can find the offset pot, give it a squirt of switch cleaner and see what happens! (MM0RKT)

Sprayed R29 on the oscillator mixer board, closed back up, hooked back up and bingo! (KM4FO)

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