Bad Channel...

the right channel was dead. This is usually an easy fix. You think... "ah, it's just a bad resistor or transistor".
Well... this channel was a mess. I think something must have gotten slopped down into the unit and shorted out a bunch of stuff. I pulled the transistors off the board one at a time, and tested each. I found three bad transistors. Then I started with the resistors... again, three bad resitors.  Lucky for me, I had direct replacments on hand. I tested the main output trannies on this channel and all seem good to go...
I got the strangest pattern... one half of the form was randomly clipping and jumping about. So I took the channel out of the unit and went over it again, but did not find anything. I decided that one of the main output trannies must be screwy. I had a matched set of Toshiba outputs. These are a direct part number replacements (2SD427 - labeled "Toshiba"... guess who made the Original "Marantz" transistors... ). So I dropped them in (both channels... I would not break up a matched set). This fixed the problem.  The unit is producing 102wpc... too cool !!!
Right and Left chennels displayed with inverted left chennel so you can see them both.

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