Hi,
I repaired one of these units last fall. I couldn’t find any schematics either, so I had to draw the circuits out myself.
These units were designed with Germanium transistors and all components were mounted on peg-boards. Quite the task !
If the unit won’t start up at all, check the Circuit Breaker first and then the Power Supply/Power Amp unit.
It is mounted on the floor of the cabinet and you can extract it fairly easily.
Working on the Radio/Preamp section was much more difficult.
In the unit I worked on, the speakers needed to be replaced, but I was able to find some Goldwood speakers in the $200-$300 range that sounded pretty nice.