RX Module - I/Q balance question #rcvr


Lexa, OK1DST
 

Hi friends,
I just finished Reciever module with ProgRock kit as LO.

My intention now is to use it as SDR rx for IF output from my K3 and TS-850 and use with CW skimmer.

So I have LO on 8.195x4, rf input directly to T3 (w/o band-pass filter) and cennected I/F out from K3 - everything seems to be OK.
CW skimmer is decoding signals but there are some "ghosts" from opposite sideband. Need for I/Q balance adjustment.
I jump into I/Q balance window (as part of CWSkimmer application) and no data there :-(  (there are empty graphs for phase/gain).

So I tried to connect PM-SDR unit (same levels, same input frq etc,, same cabling and sound card for I/Q,...) and I can see data plots in Phase/Gain graphs and calculated balance. And traces on CW skimmer are w/o ghosts and all is perfect.

So at summary - I am not able to perform automatic I/Q balance with my RX module and looking for any advices/experiences. I am quite sure I made T3 correctly with correct orientation and phasing (as unit seems to produce correct I/Q signals). I do not know if there can be some other source of so big phase/gain shift to be out of range of this automatic algorithm in CW skimmer or...?

Thanks for any advice...
73!
Lexa, ok1dst

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