In my experience (sample size of 1) The 930 definitely switches faster than
the 220, even with the big relay in the 930. You can see this because the
first dit of each CW transmission shows high SWR, indicating that the
transceiver output is not properly terminated.
The next thing that happens is that the receive side (normally-closed)
contacts on the transfer relay get cruddy, and begin to stick. The symptom
then is that the high-SWR condition lasts longer and longer. Cleaning them
restores proper operation, but the real cure is either to transfer before
the RF gets there, by whatever means ... For the moment, I'm using the PTT
function of TRLog, which actuates the PTT and the amp relay a programmable
amount of time before the first CW is sent.
I have not seen the arcing and other problems that Phil describes, even
during severe bouts of this phenomenon. The only time I experienced arcing
during the CQWWCW was when I accidentally set the loading too light on (I
think) 20 meters. Arced from the top of the parasitic suppressor to the
case! Gotta get a bit more clearance there! Or maybe that's preferable to
either the tuning cap or the bandswitch ;^}.
Phil, I'm curious about the pin diode solution -- I had heard these are
very prone to failure if the antenna SWR goes high for whatever reason -
like absent-mindedness at 4 PM on the second day of CQWW. Is there a way
to make them more bullet-proof? Does Ameritron do it right?
73, Pete Smith N4ZR
n4zr@contesting.com
"That's WEST Virginia. Thanks and 73"
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