"Do Little2" wrote in message
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"Arfa Daily" wrote in message
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"Do Little2" wrote in message
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In my opinion, it simply is a question of waiting for the digits to
settle down or to read the analog meter of that old Cap Wizard
quickly and directly.

For general service work, one finds that 3 % accuracy of the full
log scale is of little consequences with today's electrolytes and so
the Cap Wizard wins again by speed alone. :-)


I don't get where this speed thing comes from. I've seen people mention
it
before.


That speed thing came from the not so far away past, when some
people starting to say "it has to be digital, we don't want analog
meters."
Of course, at that time (end 1970's ?) they had lots of time to mention
that while patiently waiting for the slow update/ADC on their digital
meter displays.


You don't have to wait for anything with the DSE Genie. It reads "
00 ". You stick it across a cap, and before you can switch your eyes from
the cap to the display, it's reading " .80 " or whatever. No speed issue.
No ambiguity. No waiting for lights or needles to settle. No waiting for
digits to settle. Point eight ohms. Period.

That is great!
And how does it read the ESR of a bad cap. during
temperature changes? Can you read it as nice, easy
and fast as on an analog meter or does it leave you
guessing during ESR changes?



In three years of using a DSE Genie, mostly daily, for professional repair
work, I've never found

" Reading the ESR of a bad cap during temperature changes "

to be an issue. Every electrolytic cap that I've ever found to be faulty as
a result of bad ESR, is at its worst when it's cold. Many switch mode power
supplies will fail to start from cold, due to a cap with a poor ESR, which
is readily and quickly found with an ESR meter, but will start if the
suspect cap is heated first. Likewise, heavy hash on a supply rail due to a
high ESR filter cap, is always at its worst when the supply is cold. Even if
ESR change with temperature was relevant to locating a bad cap, a change
from 25 ohms to 10 ohms still represents a bad cap whether you take the hot
or cold reading. I suppose at a pinch, you could use the change of reading
with temperature to 'predict' caps on their way to failure, but in 20 years
of dealing with switch mode power supplies, which is where the majority of
poor ESR issues come up, I've never found this sort of predictive failure
trend checking, to be required.

As far as your reasons for bringing up the speed issue goes, it seems to me
that in electronic terms, 25 years ago is most certainly not the

" not so far away past "

It is actually a lifetime ago, and of no relevance whatsoever to this
discussion. Whilst back then, digital meters were slow, for the reasons that
you have stated, this is not the case now, and hasn't been for the last 10
years at least. I would restate that the digital read, calculate and display
function of the DSE meter is at least as quick as the time it takes for an
analogue meter to climb and settle, and probably actually quicker - and
without any potential reading ambiguity that is inherently associated with
analogue displays.

Don't get me wrong, though. I have nothing at all against analogue meters. I
have a good old AVO 8 Mk IV on my bench, which is used for fault finding
every day, and I love it to bits. I was originally issued with it as an
apprentice, 35 or more years ago, and I would not part with it for the
world.

It would be interesting to see what others have to say about their
experiences with analogue versus digital ESR meters, and whether they find
capacitor temperature to be a significant factor in their daily use.

Arfa