I show how I've added a second BPF on my blog:?
In a follow up post I showed how to add a second LPF as well. Only problem is that after much testing I've found it doesn't work well. I have redone it as shown here with a socket compatible with the QRP Labs filters:
I even went so far as to rebuild the original Bitx40 LPF on a a board and reinstall it. I'm going to do the same with the BPF section of the circuit (make it pluggable, single band) and just move filters around to get to the band I want. I could probably do mass amounts of switched BPF/LPF's if I wanted, but I actually don't want. I'm going to modify my case so that the top comes off easily and I can change bands in under a minute. To me that seems like good enough without getting crazy. Dual band would be nicer, but this is plenty sufficient.
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Ryan Flowers W7RLF
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