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The first thing is that all this still needs to be tested to see how well it works by someone with good test equipment. Warren volunteered since he has a very nice setup and I'm sending him parts. My old Marconi from the 70's just won't cut it.
Both the 6x filter and 4x filter boards are dimensionally set up to accept the QRP Labs footprint plug-in LPF and BPF filters (1.5" x 0.5"). This is to allow users to use those LPFs or design their own. The QRP Labs LPFs will handle 10W, the QRP Labs BPFs won't according to Hans Summers. Since I wanted to use the components off the existing uBITX for the LPFs and Hans does not provide a "blank" LPF board, I laid one out (attached) .....works out to 16 LPFs per "standard" 100mm x 100mm panel.
ALL the LPF components were moved over from the uBITX board, toroids and capacitors and placed in the same locations on the blank LPF boards. The relays can also be brought over but only on the 6x filter board because it's larger. I wanted the 4x LPF board to fit in the existing uBITX location so had to go to a smaller relay. I happen to have a qty of Omron G6H-2F relays but they are 5V so I'll have to regulate off 12V .....no problem. I'm sure there are similar sized relays out there that are 12V.
Yes, the boards are all mine and I'll make the Gerber files available once it's determined that this will work. Someone may sign up to provide boards, parts, kits. .....or you can share with others.
The idea with the 4x LPF design is to use the existing Raduino code, no changes required. However, if the 15m/12m/10m LPF is changed to 12m/10m only .....and 15m is picked up on the 20m/17m LPF (see below plots) a
small change will be required. Just don't know yet.
Hope that answers your questions.
73 Kees K5BCQ