Re: AVO VCM MK3. Meter needle not moving when switched on.
Yes, R19 doesn't connect directly to the meter in the tester, the simplified schematic I did was just to show the general layout of things without having to show all the switches being shown and from that you can see on the full schematic what connects to what.
Basically the circuit is that of a full wave rectifier, the full wave voltage is needed to deflect the meter needle to the Set area on the meter scale but in effect only half of that voltage is used when doing a valve test, that's because the valve only conducts for one half of the cycle.
Lawrence.
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