Capacitance Measurement Question

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Original poster: "by way of Terry Fritz <twftesla-at-uswest-dot-net>" <Tesla729-at-cs-dot-com>

Hi all,

Hoping everyone had a Merry Christmas :-) One of the items of
my Christmas wish list that made it under my tree was a new
DMM that could measure capacitance. Yes, up till now, I've done
all of my coiling measurements without the benefit of a means for
measuring my caps. The DMM is a Velleman made in China and 
was pretty cheap, but it seems to work well and I'm sure it will suf-
fice for my needs :-)

Now to my question. I noticed that when measuring the capacitance
of my various capacitors that there will often be a variability in the 
measurement readings that I get on the same capacitor from one 
reading to the next. It seems that it can vary by around ~ 10% or so.
I'm figuring that the difference in ambient temperature can cause a
drift in the capacitance. It is ~ 70* F in the house and around 30*F  
outside (yesterday). One of the coldest Decembers on record in my
area has made experimenting in an unclimate-controlled shop a lit-
tle uncomfortable (I do have a small kerosene heater). I noticed on the
manual with the DMM stated that the calibration is guaranteed for a
year, when the ambient temp is kept in the 18*C to 28*C range. So
maybe cold temps affect the accuracy of the DMM itself?

I thought I would throw this question out to the list as there couldn't
be a more authoritative think-tank out there regarding this matter :-)

David Rieben