2020-03-05

Analog Vs Digital Multimeters.

When should one use analog, and when digital meters for (mainly) voltage and current measurements?

To me there is an easy answer.
If I am adjusting something for maximum or minimum values, the analog meter wins every single time. It is much easier to see when the max/min values are reached with a "moving needle" meter.
Will I go without the digital multimeter? No way. It makes for an easy measurement of more or less static values.

So yes, I have a set of digital multimeters with Volt/Ampere/Ohm measurement, and one with capacitance measurement.
A cheap Chinese PCB module serves as L-C meter, down to most of the values I need to measure, about 1pF and some nH (I need to test the latter).

I just took out 2 museum pieces: Unigor multimeters. Good quality analog meters for V/A/Ohm, all the way into the Mohm range. The only thing is the battery needed for resistance measurement. Most modern meters use AA or AAA cells, or a 9V battery. Those 2 meters use 1.5V D-size cells. Now I need to find out if I can still get those. If not, I will have to find/make an adapter.
OK, the resistance measurement on the analog meter is not that important, but why not restore the full function of those museum pieces?

Apart from the multimeters I still have 3 excellent analog meters: An AC (milli)volt meter with high impedance input, a DC (milli)volt meter, and a Bolometer with a thermistor probe for up to 10GHz, one that needs care, not exceeding 10mW input to the probe, in order to keep the meter functional. More than 10mW, even for a short while, and the probe burns out.
A set of older (second hand) attenuators (for use with the Bolometer (power meter)) will have to be tested, but I have some, at least, new ones that should be good for low power measurements, up to 1/2 - 1W.

With access to the test equipment I should now be able to do a bit of home construction activities again, be it kit building or fully home made circuits.

Update:
I found an adapter for mounting AA batteries in the Unigor meters.
One of the Unigor multi-meters is now in working order. Ranges:
10uA - 1A
100mV - 1kV (DC and AC (the AC is probably not precise in the lower ranges))
Resistance measurement not very precise, but for that the digital multimeter will probably work better.
The other meter probably requires disassembly. If I get it back in order, I can measure up to 10A with that one. This is for later.

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