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Marantz 1200b no audio

Update,

upon further checks, here are my voltages on some of the transistors with Q510 and Q511 removed as well as the output transistors.

Q501 B: -0.81v, E: -0.78v, C: 17.6v
Q502 B: -2.1v, E:-0.78v, C:17.7v
Q503 B:17.5v, E:17.6v, C: -16.8v
Q504 B:-16.9v, E: -17v C:-16.8v
Q507 B:50.3v, E:50.8v C:50.8v
Q508 B:-50.2v E: -50.1v C:50.2v
Q510 B:51.1v E:-2.4v C:51.1v
Q511 B:50.2v E:-2.4V C:51.1v
Q518 B:16.4v E:16.92v C:-0.57v
Q519 B:0.05v E:-0.57v C:16.4v
Q520 B:-7.34v E:-7.96v C:-0.77v
Q521 B:50.8v E:50.8v C:50.1v

The relay clicks on in this state, however the voltages in several points are off. when Q510 and Q511 are in place the relay will not engage.

Any help would be appreciated.
 
Schematic says that Q521 should be B 0v E.7v C -.7v. You have 50volt getting through maybe Q507 or Q510. I would check Q507 first. Just a guess.

Tony
 
rickl said:
Don't forget to test all the resistors. I printed out the component board and highlighted the ones that tested good. Most will test ok in circuit but some will need a leg lifted.
Click to expand...
That's a good idea, I will do this and update tomorrow. Thanks for ideas.
 
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