>At 10:43 AM 2/6/96 -0500, you wrote:
>(stuff deleted)
>>The outside switching box
>>uses 3 relays and lets me select any of 7 antennas (plus grounding them when
>>power off).
>>
>.... But 3 relays choosing among 7 antennas
>and grounding the unselected ones to boot -- wow. ...
>========================================================================
Sorry - I screwed up when I said the antennas were grounded when it is off.
I remember now that only the coax (center plus shield) going into the house
is grounded when I switch master power off. All the incoming lines from the
antennas have a small spark gap that I built onto their coax connectors
where they enter the box, and of course their shields are grounded already
as they enter the box.
Incidentally, the Last relay in the "chain" is 4PDT, which provides the 8
output connections. You can control all this with common 3-wire #14 house
wire plus the shield of the coax for return.
Jerry W4UKU
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