> I swapped the Fluke to continuity mode, which carries a small current, a=
nd applied the probes to the terminals of the VU meter. The needle jumped a=
round as if it were possessed. It will now peg to the right, on record, but=
only goes to -4dB on playback.
OK, so it was mechanically out of the bearing or stuck somehow. Pinning it =
probably bent the needle. You're being a bit of a bull in a china shop.
The difference between record and playback probably depends on other factor=
s, like the type of tape the machine was calibrated for and how the tape ty=
pe switches are set.
> I'm not sure, but it may have always behaved that way. The unresponsive n=
eedle problem is rectified, but the mystery isn't. I wonder if anyone can t=
ell me why the needle moved a small amount when shaken, but required 'cardi=
oversion' to do its job properly? Is it simply a matter of spindle lubricat=
ion or something else? Cheers, Greg Winterflood.
No lube, it's a jewel-type bearing. You'll want to adjust the mechanical ze=
ro of the meter--where it sits when the power is off. There may be an adjus=
tment near the spindle bearing for that, or not...
Matching record and playback levels is calibration, and that requires test =
equipment and a service manual. Refer to qualified service people.
But digital recorders can be had for what it would cost to rehabilitate it,=
and they will make much better recordings.
-Dan
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