Rich says;
>The max allowable inverse for a PIN diode is c. 1000v.
Although higher voltages are available, they aren't cheap. I'm not totally
convinced of the reliability under ham conditions at any power either - I once
lost the PIN in the XYL's 2 m 25 watt mobile rig from lightning induced EMP. I
asked George, W2VJN, of International Radio/Top Ten Devices about this topic a
year or so ago, and at that time, he didn't feel that a PIN switch reliable
enough under ham conditions was a goer.
1500 watts in a 50 ohm system with an infinite VSWR is only (!) 775volts peak,
however. That appears across the diode that is switched off, though, and more of
a problem is that the current through the ON diode, which is about 11 amps peak,
(under infinite VSWR) so that you need a diode with a long trr and even then, a
pretty substantial forward bias on it.
Personally, like Rich, I stick to relays, although I have got some stud mounted
1kV long recovery time PINs intended for HF work - maybe an experiment one day.
73
Peter G3RZP
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