Quite reasonable matching can be obtained when using the normal ceramic
switch wafers by mounting them above a ground plane of PC board - stand
them off with 1/16th inch insulating washers and connect the coax shield to
the ground plane right up at the switch. But if you're putting in a matching
network, you can tune out the problem. I use this technique for antenna
switching, and the SWR gets low enough for me (<1.2). in fact, the SWR is
dominated in my case by the antennas. The important point is to ensure that
you don't live switch, as you change the switch the first time you do it if
you run any power.
73
Peter G3RZP
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