[Elecraft] K3 and sticking amp T/R relay

Gary Smith Gary at ka1j.com
Sun Oct 28 16:09:25 EDT 2012


My newly acquired 30 year old amp comes with QSK. As there was a 
different relay than came stock I have to assume the circuitry may 
have been altered in the past. I have no way to know this.

After two weeks of normal amp behavior I found the T/R vacuum relay 
had locked in the transmit position. A gentle tap on the NO terminal 
released it and function is back to normal. Mostly normal as I do 
find the ALC idiot light is no longer illuminating and the grid 
metering response appears attenuated but the amplifier puts out full 
power with absolutely no difficulty in that 35W drive gives 1500 out 
to the LP-100A watt meter.

My question for here is; if the amp is not properly sequencing with 
the K3, what setting can I change within the K3 to provide more time 
for the amp's relays to close before the K3 transmits? I remember 
there was a feature to allow ms changes for QSK in the K3. How do I 
find that option? And should I decrease the MS time in the K3 or 
increase it to let the perhaps relay in the amp have time to close 
first to avoid hot switching?

Thanks,

Gary
KA1J


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