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Re: #QMX #BPF problems with fault finding #qmx #bpf

 

If you haven't, try a factory reset and retest.

-mike/w1mt


On Fri, Sep 1, 2023 at 6:35?AM Marek SP9TKW <sp9tkw@...> wrote:
Hi All,

I hope you can help me to track down problem which I have with my BPF on newly build QMX. QMX is working ok and it is transmitting 3.5-4W at 9V, I also made QSO on 40m band.

Issue I have is that I can hear only strong stations where signal on my other rig is S8 or more.

Looking at my BPF plots at terminal I can see that I have big suppression on the bands from -30db to -50dB. I think this explains why my QMX has low sensivity.

I cheked capacitors C401-404 values and location, as well as resoldered coil L401

Here are key graphs and some photos of the board.

Any pointers would be greatly appreciared.



---------------------------------
73 de Marek SP9TKW

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