You need dwell, tach and a low ohms range of about 10 ohms as well as the
usual voltage ranges. Personally I don't have much use for current ranges,
it is all to easy to damage the instrument. Digital meters give absolute
readings without having to interpret the position of a needle on a scale,
but with varying voltages e.g. ignition it may continually hunt between
several readings none of which make much sense. On an analogue meter
varying voltages are displayed as a more or less steady average which is
more useful. If you cannot get an analogue with a 10 ohm scale get a
digital with one and get a test lamp as well. In fact get a test lamp
anyway.
When looking for bad connections measuring voltage on a wire or component
that isn't under load is no good, the meter will always show 12v unless it
has pretty-well a full disconnection. Either the circuit must be under load
when you measure the voltage or use a test lamp in place of the meter - the
test lamp will indicate a bad connection by glowing dimmer than it should.
However even a test lamp is no good on the heavy current (starter) circuit
because resistances too small to affect the test lamp will cause slow or
non-cranking, you have to use a voltmeter and measure the volt-drops *along*
the circuit.
*Never* look for a drain by connecting a meter on a amps scale in place of
the battery ground cable, if the drain is bigger than you expect you can
damage the meter. Use a test lamp to indicate a significant drain (if it
glows at all it is significant) or a meter on a *12v* scale to show very
small drains. If the meter shows less than 12v it is very small, it it
shows 12v it could be a significant drain.
When you get round to sorting your car you might like to have a look at the
web site below - select 'Spanners' and 'Electrics' where you will see a
number of options including 'Bad Connections'.
PaulH.
http://www.mgb-stuff.org.uk
----- Original Message -----
From: Phillips, Frank <fwp@ufl.edu>
To: <mgs@autox.team.net>
Sent: Friday, June 09, 2000 3:48 AM
Subject: Multimeter
> My new 68B has several electrical problems that I need to correct. I plan
to
> buy a multimeter ASAP! What features are a "must have" for MG electrical
> work? Anyone have a Sears Craftsman they like? I would like to keep the
cost
> under $60. Thanks...
>
> Frank Phillips
> 68B
>
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