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Re: Warm up time on old capacitor checker



Original poster: Ed Phillips <evp-at-pacbell-dot-net> 

Tesla list wrote:
 >
 > Original poster: "John Richardson" <jprich-at-up-dot-net>
 >
 > Hi,
 >
 > This is directed to a few of the old timers out there.  I have an old
 > hamfest Heathkit capacitor checker, and was doing some MMC readings last
 > night.  It didn't even want to register anything on the green eye until it
 > warmed up for at least ten minutes!  Is this normal for these things?  I'm
 > used to new stuff, where results are instantaneous in this solid state age.
 > Each of my 942 series caps measured out at .15 on this old thing, and a
 > string of 7 measured about .02, even though it should be about .0143.  Do
 > you think that this is accurate, or is my "Ten Minutes to Warm Up Heathkit"
 > off a little bit?  I'm not disappointed if it is, as it was only fifty
 > cents.  One more question, since this is directed at the old timers:  How
 > old is our oldest list member?  I recall John Couture mentioning that he
 > turned eighty five this last year.  It amazes me that the demographics of
 > this hobby are so wide.
 >
 > Thanks,
 > John Richardson

	A few more details please.  The slow warmup sounds like a leaky
capacitor or an open resistor (actually one which has increased greatly
in resistance).  Sounds like a bridge-type unit if it uses a "green eye"
as an indicator.  What scale were you using for the measurements?  I
would expect the thing to be good to around 5% or better and the reading
for 7 in series sounds too high.

Ed