Thanks Stan. I did not realize that the RF dB values are using a common offset. That means that the RX performance on 17 isn't that different between BPF1 and 0 - only about 3dB. I decided to try removing one more turn from 401a, and here are the results (after a few different attempts at bunching/spreading:
Looks basically the same to me. I did try a version with very close bunching of the turns, but that only gave me 1db more of peak at 15m and moved the top of the curve to the left of 21mhz. I am kind of surprised that the BPF shape and amplitude are relatively insensitive to the number of turns on L401a. Makes me think there might be some other factor at play that's driving the filter response. In any case, I think I'm ready to chalk this up to issues with using a Rev 1 board in a different manner than intended. Unless, of course, you and/or others on the forum have any ideas about how I could squeeze a bit more performance out of 15/17m receive. Either way I appreciate your help and the wealth of knowledge on this forum
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Alex N7ADH
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