might be surprised and they have a replacement pcb.
need the pcb part number to look it up. will depend if it is a 2 pcb or single pcb ln7.
2 pcb will be gone. single pcb might still be available.

 

It's a single PCB.

Since I wasn't getting DC output to the motor, I decided to test the diodes which rectify the a/c to d/c. I found 3 definite bad ones. Once I de-solder them to read the part number I can order a bunch of them. They should be super cheap to buy. I might just replace every single one of them while I have the board pulled.

Should probably find some replacement capacitors to replace the old yellow ones. I'm sure they were good in the 80s but I suspect they're at the end of their lives or already gone. Only way to really test them is when they're de-soldered and out of circuit so might was well replace when they're out.

Also there are two slightly burnt looking white ceramic high capacity resistors at the bottom. Part of the yellowing color might be from enamel, but IDK. I know resistors normally get very hot, so I don't think they're bad, but it's the only area on the board that looks to be heat affected.

Andy