Hi
I have built the filters and they work fine.
My data matched W3NQN's.
Alignment requires a sweep generator set-up.
I did not use #15 wire.
I used various NP0&RF rated capacitors to obtain desired values.
Capacitors were matched with C-meter.
Core winding is very critical.
Some of the cores were from W3NQN,some from Amidon Associates Inc. in
California.
I would contact W3NQN he has made improvements since the article
was printed,also see if he will sell you a wound core as a sample.It was
big help.
Good luck&have fun.
Paul W2TAU
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