You can find all the details on the ARRL web page, its a freebie
download. These are the original W3NQN articles.
If you dont need bandpass filter characteristics and you do want
greater suppression of your second and greater harmonics, look at the
optimised CWAZ single band filters. They single band filters whose
second harmonic suppressions are much better than the typical chebysev
filters. They would meet the FCC requirements for extreme power. I
think from memory plateaus out at 60 db on HF which the CWAZ will
suppress. The article can be downloaded from the ARRL web page. The
information is also in the latest handbooks
You can also look at the diplexer filters by Bill W0IYH, the diplexer
filter has some unique advantages at the ouput of a high power
amplifier. It can prevent harmonics from being reflected back into the
PA. Harmonics are terminated into a load resistor.
ON4UN's Low Band DX Handbook has some details for constructing series
tuned individual band traps placed in series, that go beyond the needs
of multi-multi contesting environments.
Without a network analys/zer constructing these filters are difficult..
If you dont have access to one you might look at the new IW3HEV VNA.
Craig
VK3HE
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