Hi,
I had a moving coil multi-meter when switched to the 1x range for measuring resistor, there is a voltage of about 2v at the probes, does it mean it's no good ?
How I find out :
I was testing a speaker protection circuit where the speaker is grounded before the circuit is switched on. It also had a cut off protection whenere there is a DC voltage of over 1.5v appears at the speaker output of the amp. So I clamp the 2 probes at the amp. and speaker. terminals and start throwing the power switch but of course the relay never close becase there is a DC voltage supplied by the meter!!!!! I was lucky enough that during my repeat trails that I forget to probe the terminals and the indicateing leds turn on and when I probe the terminals again, the relays didn't close anymore. Thats when I suspect that there is something going on with my MC meter and measure the probes with another DVMM and find out the problem.
So is my MC multi-meter still usable? The only ocassion that I think it got trashed is that I once had it measure some current (ammeter@250mA fill scale) and the coil swing all the way to full deflection.
Tks for your input.
I had a moving coil multi-meter when switched to the 1x range for measuring resistor, there is a voltage of about 2v at the probes, does it mean it's no good ?
How I find out :
I was testing a speaker protection circuit where the speaker is grounded before the circuit is switched on. It also had a cut off protection whenere there is a DC voltage of over 1.5v appears at the speaker output of the amp. So I clamp the 2 probes at the amp. and speaker. terminals and start throwing the power switch but of course the relay never close becase there is a DC voltage supplied by the meter!!!!! I was lucky enough that during my repeat trails that I forget to probe the terminals and the indicateing leds turn on and when I probe the terminals again, the relays didn't close anymore. Thats when I suspect that there is something going on with my MC meter and measure the probes with another DVMM and find out the problem.
So is my MC multi-meter still usable? The only ocassion that I think it got trashed is that I once had it measure some current (ammeter@250mA fill scale) and the coil swing all the way to full deflection.
Tks for your input.
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