One thing that I found really helped "bouncy" brand new meters on a
Centurion amplifier was to put a 3.9 volt zener across the meter terminals .
(This obviously only works on a high resistance meter movement like these
that are about 2380 ohms with FS of 1 ma so have about 2.3 volts across them
full scale - a bonus is meter protection as well.) What appears to be
happening is the "forward" 0.7 volts diode in the zener conducts when the
meter tries to swing back due to the reverese voltage and really damps the
movement. Far superior to shunt capacitor approaches.
A lower voltage zener like 3.3 or even 2.9 would probably give somewhat
better meter protection but 3.9 was what I could lay my hands on when I had
the amp opened up.
YMMV - Hank K7HP
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