W0UN -- John Brosnahan wrote:
> I, too, was disappointed to hear that the 9500 was going back to a vacuum-
> relay-based QSK system since I have been very happy with my Alpha 87As
> and have never had any problems with PIN diodes after Alpha sorted out the
> issues for the Alpha 86 T/R switch update.
I just want to add my own anecdotal evidence and prejudices here. I had
an Alpha 86 (apparently updated) for a couple of years with absolutely
no PIN diode problems, and I operate QSK cw exclusively, even in
contests. All my antennas are fed through DC-ground type lightning
protectors, which might have helped as John suggests.
I've also used vacuum relays in several amplifiers with Rich Measures'
speedup circuit. I once had to replace a Jennings RJ1a; the failure
mode was that the receive contacts became unreliable. I had a Kilovac
HC1 which worked fine for several years in an SB1000 and as far as I
know is still working for the guy who bought the amplifier.
Finally, I think that the smooth, quiet t/r switching of a QSK system is
worthwhile even for SSB operation or semi-breakin CW. I wouldn't have
an amplifier without it.
--
73,
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|