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Old February 3rd, 2012, 12:52 PM   #72 (permalink)
Commodore 64
Tele-Afflicted
 
Join Date: Mar 2010
Location: Kent, OH
Age: 37
Posts: 1,864
Rock Mumbles helped me troubleshoot my 5E3. I don't have a rectifier tube in mine, so I dunno what to look for on that thing. But this should get you started:

Plug the amp into a speaker. Turn it on.

Stick the black probe on your common grounding point. Put your left hand in your pocket.

With your right hand, put the red probe on:

6V6 voltages (measured referenced to ground):
Plate pin 3
Screen pin 4
Cathode pin 8

12A_7 voltages (measured referenced to ground):
Plate pin 1
Cathode pin 3
Plate pin 6
Cathode pin 3
pin 2 on V1 should give speaker noise.

For the Heaters carefully measure between pins 2 and 7 on the 6V6 or between pin 9 and pins 4&5 on the 12AX7's. You need both hands and both probes, one probe on each pin in the pair, this is AC. Be careful.

Report back with numbers.

My Fluke auto-range DMM was a godsend, so I didn't have to keep flipping the dial.
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