[Collins] Help with 75A-3 meter

[Jim Brannigan]

R67 is a 100ohm resistor across the meter.  Put that in and retest.  The
S-meter is in a bridge circuit between IF amps V-5 and V-7.
Jim


> Hello All!  I'm in the middle or restoring a 75A3 (ser# 1147) which had
been quite mis-treated in some earlier day (to include being home to many
bugs e.g. insects!).
>
> I've managed to bring it back to life, but am stumped by the S-meter.  It
pins to the far right when the rig is turned on, and remains there.
>
> I have checked the following components:
>
> R47, R50, and R49 (variable and checks fine).
> I can't find R67, although it is listed in the schematic.
>
> All tubes check OK.
>
> I get a minimal voltage reading across the meter. Actually about 1/2 volt,
which does not vary.
>
> Since the realignment requires, and is a bit easier, using the S meter
reading, I'd like to get the bugger working.
>
> Any suggestions would be very welcome!
>
> Thanks,
> Bob
> W1CNY
>
>
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