Re: AVO Multimeter survey
Mike, that is a June 1954 meter, quite a late one. The later ones have slightly more attention to detail in the manufacturing, i find- so it is certainly worth having.
If only the 5 volt range is working this suggests the 25volt bobbin may be open circuit, the favourite quick fix to this is to solder in a resistor instead. (removing defunct bobbins is a bit of a faff and liberates flakes of debris into the meter, i prefer to leave them in place, and piggyback the new resistor, sat on top of the bobbin.)
The circuit is fairly simple, i think there may be a handwritten one on richards radios, but in any case i am quite happy to locate the fault if you want to bring it over. It sounds like a simple one to fix.
Personally,I would remove the battery pronto if it's an oldie!
Dave
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