> I'm sorry, but I disagree. An analog meter is much preferable to
> troubleshoot
> car problems. You can watch varying voltages/currents/continuity
> that a DVM (or
> DMM) can't.
Only takes a more expensive meter to have response times comparable to an
analog meter (whose response is not instaneous either). It's true the
cheapie units are slow, but it's also true I rarely have any interest in
rapidly varying signals, beyond noting that they vary rapidly. And even a
cheap DVM will indicate variations are occurring when they are too fast to
see on an analog meter. If I need to know more, I get out the (digital)
oscilloscope.
And the first time you forget and leave the meter on ohms when you connect
it across the battery, you'll see a big advantage of a digital meter.
> You can see any inductance/capacitance issues in
> wiring,
When's the last time you had an inductance or capacitance issue in car
wiring ?
> if a diode works properly,
Even my HF cheapy will do diode test. Better yet, it has an audible
continuity indicator, which is a godsend when you're laying on the back of
your neck under the dash. Very few analog meters have that.
> the timing of open/close of relays/switches much
> better.
Oh yes, very important in a car. Not.
> As far as loading down a circuit, a meter is rated in ohms/volt.
Only analog meters are rated in ohms/volt. Digital meters almost always
have a fixed input impedance, because of the way they work.
> BOTH the cheapy digital and analog versions are
> normally rated at
> around 20K ohm/volt.
Simply not true. I have a HF cheapy ($5 on sale) DVM in my hands, with a
constant input resistance of 1Mohm, even on the 200mv scale (for an
effective 5000K "ohms/volt").
> So a cheap analog meter won't load a
> circuit any more
> than a cheap digital version.
Again, not true.
But the big reason I like to carry a cheap digital in the trunk is simple
... an analog meter, even an expensive one, simply will not survive long in
that environment. They are much more sensitive to shock, vibration and
moisture, all of which are found in abundance in my LBC trunk. The last
analog meter I tried to carry in my TR3A lasted less than a month, while
I've carried a HF cheapy DVM for over 10 years now and it still worked fine
when I pulled it out of the wreck.
I've got analog meters stashed away in my garage, but I haven't had one out
to use in many, many years. A DVM does everything I need to do on a car.
Oh yeah, one other thing, cheap DVMs are a lot cheaper than cheap analogs.
You just can't buy a new analog meter for $5 these days. (In fact, buying
analog multimeters at all is getting hard, there's just no market for them.)
Expensive DVMs are still cheaper than expensive analogs, too, not to mention
much more accurate.
Randall
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