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Old 17th Sep 2022, 1:42 pm   #3045
The Philpott
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Join Date: Aug 2016
Location: Colchester, Essex, UK.
Posts: 4,081
Default Re: AVO Multimeter survey

Post 3043- Model 9/II

Pthomas, those resistors are high quality so it probably had been overloaded at some point to generate such a drift, i reckon. The rectifier will have been replaced at some point, it would have started life with a copper oxide one with the general appearance of one of Barnes Wallis' bouncing bombs.

There's a graph (in the Model 8/III manual) which details AC frequency response on two selected ACV ranges, and it shows that this generation of meters are outstanding in this respect, even by more recent standards.

Your meter may soon be getting to the age where the leather strap starts to react with it's holding rivets, and hardens up. Keep an eye on this!! Once the nickel plating has worn through the brass and the leather affect each other in a negative way.

Dave
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