More of the same.
Unwound the wires from the CD-4 sub-channel decoder board.
That allowed the board to be removed for easy access. There were 3 pages of capacitors, and I didn’t feel like fighting with it.
Stripped the wires back ready to be rewound.
Into the other end of the tool.
Recapped and back in place, in record time.
EQ and preamp board popped out next. This one had wires that were long enough to flip it up for access.
EQ board done and snapped back into place.
The protection board was similarly easy to access. Pop up and redo. The 100uF 16V cap I accidentally ordered came in handy as it replaced the one I accidentally blew up on the PSU by putting it in backwards.
Pulled the power amplifier module up and out so I could pull board 2 off its’ pegs.
With burned fingers, pliers and tweezers, working in this space (looks bigger than it is, could just about get a finger in that gap) redid the 4 caps on the second board.
Clipped back in and all done.
Have amassed quite a collection.
Pulled out the service manual and started to look at the power/amp board adjustments. It stated the inputs of the amp board needed to be terminated across the pins with 5.1kOhm resistors. Wound 4 on:
Began setting up the idle and bias:
These pots are real touchy, takes a very steady hand to adjust.
All set up (as close to 0.02000 Volt that it would go).
Buttoned it back up and set it up. Played it for a couple hours, and it sounds good.
Got some parts coming in Tuesday to redo the control amplifiers.