Tom said:
>not read at all (the current path is
through the springs in conventional movements), <
many of the older meters I've come across still read even with a broken
hairspring because there's a current path through the bearing. I've found
relatively few meters with real 'jewel' bearings; the majority are steel on
steel. But, on the other hand, the majority of meters I've opened up to this
extent have been WW2 era meters, so they were probably made cheaply anyway.
The last one I opened was the other week: a 200 microamp meter on a Heath VTVM.
There was a short and the needle whipped across the scale at something that
seemed about Mach 2 and stuck at FSD with the top of the pointer bent. So I
cussed it, took the meter out, got the front off and immediately had the needle
fall back to zero and the bend straighten itself out! Occasionally, you do win
some......So if there are jeweles in that meter, I didn't get to see them.
73
Peter G3RZP
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