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.

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73, Pete N4ZR
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