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Default VOM -- How to use

On Sat, 09 Jun 2007 13:27:57 -0700, wrote:


From the manual:

Ranges: 27
DC Voltage 0-0.25-1-2.5-10-25-100-250-1000V


This almost certainly means that there will be at the far end of the
scale, opposite from where the needle normally rests, the numbers 25
and 10.

25 will mean different things for different settings of that switch.
It will mean either .25, 2.5, 25, or 250.

There will also be other numbers midrange, the same color and the same
positioning relative to the other numbers as the 25, that help you to
read lower values, probably 5, 10, 15, and 20.

10 will also mean different things for different settings of that
switch, either 1, 10, or 100, and if the 1000 volt jack is used 1000.

There will aslo be other numbers midrange, the same color as the 10,
maybe 2, 4, 6, and 8. The positioning helps you keep track which set
of numbers you want to look at, based on the swtich setting you chose.

AC Voltage: 0-10-25-100-250-1000V


Same thing as above. IIRC, on some meters, 25 for AC doesn't show up
in the same place as 25 for DC, for example, but the color coding
should make it clear which is which. Or there will be ~ to represent
AC current on the AC scale. AC scale number are usually red for some
reason, iirc.

DC Current: 0-50-500U A, 5mA-50mA-500mA


Each of these is ten times more than the one to the left. Including
that 5mA is 10 times 5uA. Stop using a capital U and use a lower case
u instead. If your manual uses an upper case U, it's wrong. (probably
printed in Japan, and no one really skilled wants the manual writing
job.) A capital mu in Greek looks like a capital M in English. Only a
lower case mu looks pretty much like a u, a lower case u. (Look in the
dictionary under "alphabet" for important alphabets.

Resistance 0-6K Omega (midscale 30 Omega)
0-60K Omega (midscale 300 Omega)
0-600K Omega (midscale 3K Omega)


This is usually measured on a different scale, with an omega at one or
both ends, the scale is usually black and closer to the pivot of the
needle than the others. It will not have a 6 at either end because
the left end is infinity and the right end is zero. There is a knob
or the edge of a knob with which to "zero the meter", by touching the
leads together and turning the knob until the needle is above the zero
mark.

Decibels (HUH I thought that was sound)
-22dB ~ +22dB ~ + 62dB in 5


It's also ratios, though I have never used and don't know how to use
the decibel scale.

For 25 dollars, you got a good meter. Not the best of course but not
junk either. Probably has a mirror? Do you know how to use that?

Sensitivity 20,000 ohms/volts DC
10,000 homs/volt AC

Fuse 0.5A, 250 V 32mm