M90 deck help ! (continually clicking)
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You appear to be running around in circles chasing your own tail. Of course the remote behaves the same way. It's a 100% parallel circuit to the onboard deck buttons. Pressing stop on the remote functions exactly 100% the same as if you depressed stop on the deck.docs said:
PRESUMING YOU HAVE CORRECTED ANY MECHANICAL ISSUES and you want to focus on electrical possibilities...............:
Take pin 5 of IC701 out of circuit by removing the solder from the pad
Take pin 8 of IC706 out of circuit by removing the solder from the pad
Verify both pins are no longer connected to pad (use meter, not visual).
CHECK LIVE OPERATION. If autoplay is no longer occuring, then IC701 is probably working OK and you may have a short elsewhere. If autoplay continues, then IC701 might be bad which is bad news since it's obsolete everywhere.
Check the following (WITHOUT POWER):
Check resistance from pad (or trace) of pin 5 (not pin 5 itself) to pin 8 of IC701. If you get ~220ohms, you have a short, likely in the play button circuit. If you get open-connection (inifinity), then restore solder to pin 5, and recheck operation. If still no autoplay, but play/stop is working, then issue could be in the timer circuit. Check Timer circuitry which includes IC706 and appurtenant components.
BTW, this is all the help I can give you Dave. Hope it's enough to set you straight. Basically, I'm swamped over my head with domestic happenings and I can't devote anymore time to this. As you may imagine, each one of my posts require significant time to study diagram, compare with your findings (which will frustrate me if I don't trust your readings), and then type up a response. Not that I don't want to, but there's not enough time in a day for everything.
What's your charge out rate Norm!? 
This thread is worth a lot of money in other words ha ha.
Scotty
This thread is worth a lot of money in other words ha ha.
Scotty
Norm thanks again as always, I appreciate all the help you give.Superduper said:
Pin 5 of IC701 and pin 8 of IC706 removed from circuit and proven by testing continuity on pad and pin.
Checking live operation and the autoplay functioning is no longer present.
Without power, the resistance between pad of pin 5 to pin8 of IC701 I think is infinity.
Resoldered pin 5 and left pin 8 (IC706) out of circuit and checked live operation - no longer auto plays still and pressing play and stop works as it should along with pause. FF/REW cause a clunk but do nothing so that's probably a separate issue.
So after this advice we now have a deck that is almost fully functional! Many thanks!
BoomboxLover48
Boomus Fidelis
Just need to retest the timer circuit including the little board with the timer switch on it and will hopefully spot something.
Thanks agian Norm for your invaluable input. I can read all the electronics books in the world and still not understand some things because learning something like this requires mentorship, something I am looking into and hopefully one day the penny will drop.
Thanks agian Norm for your invaluable input. I can read all the electronics books in the world and still not understand some things because learning something like this requires mentorship, something I am looking into and hopefully one day the penny will drop.
Looks like IC707C (record timer) is receiving voltage when switch is at off position so the timer thinks it is set to rec. When autoplaying it isn't trying to record though. When the switch is at record it shows same voltage and when it is set to play it is at zero volts as would be expected since that is dealt with by a different gate I expect.
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