Mmm.. one thing it needs, is an added DC-blocking capacitor on each of the four inputs, to prevent the +12V switching voltage from running up to my antennas (and possibly shorting out there).
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Mmm.. The reference design I found for a 2GHz switch uses 56pF blocking caps.. so perhaps I'll try something close to that.
I would put in 1000pF to be safe. Even at 200MHz, the 56pF will be about 14 ohms. At VHF channel 2 the 1000pF would look like 3.5 ohms.
Dunno if you're still around, but I'm questioning that 1000pF value again. The very sensitive, ultra low noise, pre-amp I use for UHF/VHF television here, itself uses 68pF
(with an inductor to ground), followed by 470pF on the input side.
I wonder if 1000pF is too high a value ?
Cheers
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