Don Wilhelm wrote:
<div class="moz-text-flowed" style="font-family: -moz-fixed">Rod,
If you keep it dry, electronics will store nicely for a good long time.
Temperature is not a consideration as long as condensation is
Although not as significant as when devices are under bias, the
Arrhenius equations still implies that the failure rate will have an
exponential dependence on temperature and thermal cycling will still
cause mechanical stress. I'd guess that the combination of under bias
degradation and thermal shock from operation will probably age the
system more in a few weeks of operation than two years of storage, though.
The other consideration for long storage, although probably not for two
to three years with modern components, is that eletrolytics will
depolarize; that can result in excessive currents if there is no natural
current limitation, until the oxide reforms. If the current is too
limited, it may prevent them reforming, which is, I suspect, how the
electronics in one of my cameras died when I didn't use it for several
years.
I'd guess a couple of years is OK with modern components, but it would
be advisable to power it up overnight from time to time if it is going
to be mothballed for a very long time. This is the main reason why very
old equipment, which hasn't been used for a long time, should be treated
with extreme care, as old electrolytics can explode quite spectacularly
if their oxide has decayed and they are effectively short circuit.
Modern ones are designed to break open before they explode.
Because some power lines are only active on transmit, you may need to
key the transmitter, at low power, into a dummy load, to ensure that the
electrolytics are reformed.
controlled. If it is at a temperature extreme when put back into
--
David Woolley
Emails are not formal business letters, whatever businesses may want.
RFC1855 says there should be an address here, but, in a world of spam,
that is no longer good advice, as archive address hiding may not work.
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