Don Pearce wrote:

Phil Allison wrote:
"Don Pearce the Geriatric Fool "


For a quick and dirty test, just connect a multimeter on the ohms range.
The needle should flick across to short circuit, then drop back towards
high resistance. The time it takes to drop back is proportional to the
value of the capacitor. If the needle ultimately drops back to open
circuit, the cap is probably ok.


** ROTFLMFAO !!!!!!!!!!

Hey grand-dad !!

Got any ****ing idea how long it is since " multimeters " had needles ??

Bet your pathetic old AVO has a nice BENT one - eh ?


Why don't you **** the HELL off - grand dad -

& spare the planet you dumb as dog **** WRONG advice.




...... Phil




You don't have a multimeter with a needle? You are missing one of the
best alignment tools anyone could own - and a handy capacitor tester of
course. Go out and buy one now - it isn't a replacement for a DMM, but a
very useful complement.

I have several analog and digital meters in my shed. But 99% of what i
measure is done with a Fluke DMM.

I got the analog meters for almost free at ham fests and dumpster bins.
Some I have calibrated for voltage measurement using an opamp drive with
diode in the shunt FB path so the meter reads logarithmically. These are
then calibrated in up to 30dB each side of a centre idle point, making
readings of speaker responses quite easy and accurate enough over 33
chosen filter Fo of the audio band. The signals measured are those
recovered from a pink noise source fed to the speaker, and a mic signal
amplified and filtered by a bandpass filter with Q = 12 at all F.

Its an old fashioned thing I made before I got a PC. I have not got
around to buying a Spectral analyser program to display speaker response
immediately on a PC screen, and variably as you change the mic position,
or alter a cross over component.

But it tells me 90% of what I need to know about loudspeakers. And if
the C values in crossovers were correct, or labelled correctly at the
factory; sometimes you get old "100uF" caps but they measure say 52uF,
but look perfect, and have not obviously dried out, and sometimes much
more C is there than the amount on the can. But its never an accurate
way to measure the C in crossovers, so see my other posts.

Patrick Turner.





d