Thread: Avo 8 movement
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Old 21st Dec 2017, 4:35 pm   #11
Sinewave
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Default Re: Avo 8 movement

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Originally Posted by Sinewave View Post
Also, another question, regarding another instrument, an 8 Mk 6.

When measuring VDC, the displayed reading whilst increasing the voltage is different than when decreasing.

For example, when increasing voltage, the readings may be 1, 2.....7, 8v

when decreasing, there's a difference of 200mV, so 9v can be 8.8v, 7 would become 6.8v.

What would cause this do you think?

Thanks.
Just looking at this again, what I've noticed is that in the 50 micro amp range, the movement goes to 50 and back to zero all day long, fine. I believe that when in the 0.05ma range, we're pretty much connected directly to the movement, with no dampening circuitry at all.

In any other range where there is some dampening, it's as if the dampening is engaging every so often, causing the needle to stick. A very (and I mean very) gentle tap on the case frees the needle up again.
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