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oh well, broken trace, things are not allways complicated…
Then mechanical adjutment and re-build
Well, I do not have any 0TR1, I C1 I guess..
As I say on first message newer board and service manual do not equal. Manual says “circuitry is basically identical” although layout and numbering is different. So I have to decode board with almost right circuit diagram.
Reason for 4IC1 was bad aglinment.
For slow carriage movement shorted D31 between slow back 3V adjustment and motor feed transistors.
Next problem. Carriage motor wont stop at stop switch, and yes, switch is ok.
Back on this for a moment…
On DVM transistors (TR19-22) on “ON” side base voltage is when “>” 5V an “>>” 14v but on “OFF” side (TR23-26) both “<” and “<<” app. 4V.
Also should 4IC1 collector be adjusted to 5V with R88, can adjust only to 6,5V min.
Sorry all, I have talking rubbish (poor, poor memory).
You are absolutely right, >> is weak, and does NOT depend any other keys.
Yes it is, but difference is do I press up/down before it.
Mark, I mean if record is playing, I press arm up and then fast backwards, it does barely move as there is not enought voltage on motor. If press stop, arm goes to home position at normal speed.
Martin, I know, this board picture is from my “spare” machine, I do not know if it is even in working condition. Just so lazy I did not get actual board out of player.
I do like to check transistors but witch ones? Of ourse I can check them all but to know will ease process.