I hope this isn't too far off topic. It does relate to me getting
back on 2 meters for future contests!
Is it possible to build an inexpensive SPDT solid state switch
capable of handling 350VDC 150mA that can toggle states when driven
by SPST logic? It seems like there should be a way to do that but my
feeble mind won't come up with anything. Google didn't seem to be
helping with ideas either. If anyone has any thoughts on this I
would like to hear them.
Here's the reason: I'm resurrecting and modernizing an old Swan TV-2
transverter. One of the things I want to do is get rid of the slow,
noisy open frame T/R relay. I'd like to replace it with something
reasonably fast and quiet. I already know how I'm going to handle
the sections that deal with RF switching. What's not so clear is
what I'm going to do about switching 350VDC between the receive and
transmit sections of the transverter. If I have to I will use a
small vacuum relay, but I can't help thinking there must be a better
way to handle this. Besides, the vacuum relay I'm thinking of
drafting for this task is my only spare for the QRO 6m amp!
Transistors capable of handling the voltage and current are readily
available and cheap, but I can't figure out how to make a SPDT
switch that will swap states when driven my the SPST "ground to
transmit" logic.
73,
Paul N1BUG
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