01-25-2010, 10:42 AM
I tried Terry's suggestion, placed a silicon diode across the 35Z3. Monitoring the plate voltage on the 7B7, it went up to 149V, but after a few seconds dropped back down to 39V.
Subbing a new 50L6 didn't change anything.
Subbed a 500 ohm resistor for the field, no change.
Changed C17, no change.
While touching my meter probe to the center tap of the volume control, speaker hummed, so I would say that the output transformer is good.
Not finding a short anywhere from B- to chassis.
I'm getting cross-eyed double checking the schematic. Would have been so much easier if somebody else hadn't started recapping this thing.
Subbing a new 50L6 didn't change anything.
Subbed a 500 ohm resistor for the field, no change.
Changed C17, no change.
While touching my meter probe to the center tap of the volume control, speaker hummed, so I would say that the output transformer is good.
Not finding a short anywhere from B- to chassis.
I'm getting cross-eyed double checking the schematic. Would have been so much easier if somebody else hadn't started recapping this thing.
Carl
Northern Panhandle, WV
