I intend to do a PIN switch for my next amplifier. I managed to get some
Unitrode diodes rated at 1.2kv and 1 amp - 10 wire ended and 10 stud mount
with tape leads, all with a long trr so they are good for 160. However, I
don't actually like operating QSK! Of course, switching the high voltage to
reverse bias the PINs while providing 1 amp of DC for forward conduction is
an interesting project in itself. Although the probability of an infinite
VSWR is probably low from the viewpoint of mis-tuning the tuner, an arc can
cause a pretty near infinite VSWR, so you could get twice the normal
transmission line voltage appearing.
All that has to be held while I sort out the trouble with the RCD (GCFI in
American) which trips from 80m RF. The one feeding the antenna tuner shed
has been disconnected since that tripped on 160....................while
investigating, I noticed daylight coming through the roof of the shed and
had a minor side job of replacing the roofing felt on the shed which had
rotted away. The idea of a high impedance feed with rainwater coming in to
the tuner did not appeal!
73
Peter G3RZP
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