I've seen that a few times with WSJT-X 2.1.0 using an IC-7300 as the radio, so it may not be related to the RPi.

On Jul 30, 2019, at 5:33 PM, N4ZR <n4zr@comcast.net> wrote:

I'm noticing a strange phenomenon using WSJT-X to decode FT8 messages. Fairly often, I see multiple spots of the same station in the same transmission period. Invariably, the highest-frequency spot is the loudest (and always quite strong, typically over 0 dB), and at 100-Hz intervals below it progressively weaker spots of the same station appear. Here's an example:

My setup: Carolina windom to Clifton Labs 11 dB preamp to AM and FM broadcast band filters, then to an RP-16. Software-wise I'm running Demin's SDR receiver to CWSL_Tee to CWSL_SSBWave.exe to WSJT-X.

I'd like to know if anyone else is noticing this. I've only seen it since I started using the RP-16.
-- 

73, Pete N4ZR
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