diagnosing NC183
I've been renovating a Malden Mass Monster...NC183D. It sortta
works, but the B- is supposed to be -21 volts and 500 ohms from chassis
ground acting as the bias for the audio power amps and the negative end
of the RF gain pot.
On my rig the line measures only millivolts negative and 0.4 ohms
to ground. I thought first I had a shorted electrolytic and replaced
all the caps on the line. No joy. Then I thought the transformer
center tap might be shorted to the case, so I unsoldered it and measured
it. The Xformer is very healthy but the line still measures 0.4 ohms to
ground.
Any suggestions what I should look at next?
tnx de kc2lvq
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