Hmmm. Let's put together a little thought experiment on how long an RJ1A
should last a contester.
Rich says the RJ1A is rated for 2,000,000 closures.
Lately, I've been averaging about 2,000 QSOs in the big contests. Figuring
an average of five characters in each callsign contacted, the average
exchange is about 18 characters when running stations (callsign, RST,
exchange, TU, WC1M) and about 12 characters when doing search-and-pounce (my
call, RST, exchange.) I probably do 75% runs and 25% S&P. I figure the
exchange has to be repeated about 15% of the time. If the average number of
elements per character is 3, then I end up with about 114,000 relay closures
for the exchanges.
Figuring CQs is a little harder. A CQ costs 14 characters (I like to send
"CQ TEST WC1M WC1M".) During big runs, I hardly ever call CQ. Maybe once
every 5-10 minutes at most, probably less. During slow, steady runs it might
be more like once per minute. During very slow periods, I probably call CQ
4-5 times per minute or more. Let's say I operate for 30 hours, 22.5 of
which is spent running stations. Let's say the run time is equally divided
between big runs, slow/steady runs and very slow runs. That comes out to
about 2325 CQs in the contest, or another 97,650 relay closures.
Altogether, that's well over 200,000 relay closures for one contest. Since I
try to operate in the five big CW contests each year (Sweepstakes, CQWW,
ARRL DX, CQWPX and IARU), an RJ1A relay is only going to last me about two
years! Yikes.
But I don't use QSK for running stations. In fact, I suspect that very few
CW contest operators use QSK, unless they do only S&P. Listening to loud
static, noise and QRM (and AGC pumping on some radios) between every element
can be exhausting over a couple of thousand contacts or more. I love QSK for
chasing DX, and high-speed ops love it for ragchewing, but it really isn't
all that helpful when running stations in a contest. I do like to use QSK
for S&P contacts, which are more like chasing DX. But that's responsible for
a relatively small percentage of the relay closures.
Some ops have said that they set the VOX to drop out between words. This
would cut the number of relay closures to fewer than 20,000 per contest,
extending the relay life to nearly 20 years! However, I find no reason to
listen between words, so I set the VOX to drop out at the end of each
transmission. Setting the VOX this way results in less than 5,000 relay
closures per contest, so the relay should last a lifetime.
I should add that I use an 87A with PIN diodes on the run radio anyway. But
I don't use QSK for running stations, even though I can. The amp on the
second radio has an RJ1A, but the S&P duty cycle on that amp is very low.
73, Dick WC1M
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