Mc 2505 no power

There are a couple of circuit changes with this amplifier, and several service bulletins related to it. Just so you know. I have the manuals and the bulletins if you need them on PDF scans I can share.
I am about to embark on a full restoration of MC2505 ser no 38k30.
If you have diodes and transistors replacement list as well as those bulletins, I would appreciate it. Bests,
V
 
I am about to embark on a full restoration of MC2505 ser no 38k30.
If you have diodes and transistors replacement list as well as those bulletins, I would appreciate it. Bests,
V

I would start a new thread specific to the issues you want to resolve for your MC2505.

All the semiconductors are obsolete, out of production for decades and have had multiple substitutions over the years.

Have you bench tested the unit, does it have any specific problems?

There are a number of service bullitens in the Akdatabase for these early transistor units, most often to help the techs, new to semiconductors, get comfortable with them as most of their experiences were with vacuum tubes.
 
I would start a new thread specific to the issues you want to resolve for your MC2505.

All the semiconductors are obsolete, out of production for decades and have had multiple substitutions over the years.

Have you bench tested the unit, does it have any specific problems?

There are a number of service bullitens in the Akdatabase for these early transistor units, most often to help the techs, new to semiconductors, get comfortable with them as most of their experiences were with vacuum tubes.

You are right...I will start it.
yes I tested the unit. Voltages are all over the place. I see someone had been in there and changed resistors, while in fact I believe rectifiers are about to go. Distortion on the left channel traced to be the "married couple" on the output board.

Most of the resistors are beyond the 10% limit. And capacitors need to be changed...

Huh,... I've got myself a Chrissy Pressy.
 
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