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Hi there .

I have finished my QMX LB.

?My Pass Band Filters seem to be a little high (see attached plots).

Should I try to get the center frequencies lower or are they OK as they are ??

How are others performing?

Thank you.

?

Not bad, actually. Down a couple dB from peaks..... worst case is what, 3 or 4 on 80m, which Hans argues doesn't matter much on that band due to the higher atmospheric noise.

I'd try and squeeze windings on L401(I think that's the right one on the QMX) and see if that helps at all. Squeezing turns together increases inductance, which in theory should bring the peaks down, but the BPFs are a fickle beast. If you can't improve it, I wouldn't call this a problem enough to do anything.?

For me, I wouldn't worry about 2-3 dB down from the peak.? 20 dB down like the QMX previously sometimes had problems with on 20m, sure.?

-Nate
N8BTR