Re: AVO two panel tester strange fault
I am not sure If I have mentioned this before so forgive me if I have.....
There is some debate as to whether the AVO 2 panel used the same movement as the AVO 7.
I have looked at this and have concluded that the answer is a qualified yes, at least with the early Avo 7s with the horseshoe magnet.
It is somewhat confusing as the AVO 7 is 1mA fsd and the 2-panel meter is 0.6mA.
BUT the AVO 7 meter subtends a far greater angle from 0 to fsd.
The 2 Panel uses the same movement but the angle from 0 to fsd is only 0.6 that of the AVO 7, hence 600uA fsd.
The complication comes in that the 2 panel has a longer pointer so that the reduced angle still sweeps a decent scale length.
To use an AVO 7 movement in a 2-panel valve tester you would have to find a way to extend the pointer and re-balance it by adding weight to the other end.
Peter
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