blu_fuz said:
................When I went to put it back together I crossed the +/- wires on the circuit board. It blew the two parts when I plugged it in but it had no effect on how the box functioned..............................
Oh goodness. I'd be very concerned now that the box may have other problems introduced by the application of incorrect polarity hookup. Some items like the electrolytic capacitors will actually explode if hooked up backwards. Other semiconductors can fail when hooked up incorrectly but it's not likely that they would explode so external evidence may not be immediately apparent. The failed parts you saw, you knew were bad because of externally visible evidence. Other parts may have failed and not shown physical symptoms.
The fact that it now performs like before is a good sign but not a guarantee that the reversed polarity hasn't damaged other parts. The reason is that the circuits that weren't working properly before due to problem A might now be not working due to problem A + B. Results the same but repair entirely different and complicating the diagnosis. Hope that is not the case with yours.
If I were to trouble shoot your radio, I would look in this manner:
Source of the power on/off problem. This could be related to the tape deck. If the belts proves to be broken/stretched or motor blown, that would have to be remedied first. You can certainly turn the capstan flywheel by hand to see it you feel any switches or levers actuating as you turn them. Normally, turning the flywheel several revolutions will reset the switches back to normal. If you do this and the function of power on/off is restored, then that is a great first step.
Next, you'd want to re-evaluate the performance again with the cassette mechanisms reset. Then note the problems you are having. If the problem is the same, then let's try to find out if the problem is in the pre-amp section or power amp section.
Try the line outs and hook them up to another radio. If you can hear the radio fine, and in stereo, it's a pretty good indication that the problem is in the power amp section and that the preamp section is not operating properly. OR, the preamp could be fine but the tuner board not outputting properly.
questions I would want to know:
(1) Does the tuner behave normally. I mean does the tuner signal strength indicator move like it normally would.
(2) Does the line in function work?
(2a) If yes, does it work in stereo?
(2b) If not in stereo, will both side work if it's set to either the wide or mono mode? (if you have it).
(3) Does it output a signal normally via the line outs?
(3a) If yes, does it output in stereo or is one or both sides attentuated?
None of these tests will FIX the radio but it does give a clearer picture of what might be happening.