This came in with a loud hum on both speakers, tracked to a leaky electrolytic in the power supply, no outward sign that the capacitor was faulty, I say that because people are quick to say “look for bulging caps”, well they don’t have to bulge to be faulty! So I first tested it on the built in FM radio…only one channel working…great!  Luckily I was able to download the service manual and using a scope work back from the outputs to the stereo decoder where I found the coil LP200 to be open circuit. Now the radio was working perfectly it was time to test the tape deck, no problems there so a quick clean of the heads and pinch rollers and the job was completed…except for the speaker leads, the customer had brought them with him luckily enough because they had been extended by twisting the wires together and taping them up, not even any solder involved, so I chopped the joints out and remade them with solder and heat shrink sleeving. Now back with it’s owner and working well.