anderslober
Yikes...not again!
Hello Forum.....I am restoring yet another of these nice units. This unit has a couple of problems. Stereo light will not come on(bulb is new) and at turn OFF there is a kinda' power-down crackling in both channels. Power ON is fine.
Could the crackling be a PS problem. I have just changed the caps...not the tr's. I don't have any of the recommended ztx695 or ztx795 tr's. Can other subs be used? Mje15032?
The stereo light does not come on(bulb is new). I have 21.4v on pin11 from PS....both sides of the r36 resistor have 21.4v(should be 23v/18v)......and the IND pin on MPX board has the same 21.4v. Is the resistor bad?
On c717 MPX board I have 5.5v(+ leg)....and when I tune away from stereo, I still get 5.5v.......so, I guess I there is something amiss. Sound out put is fine. Also r733 measures a constant 3.1v..(pin6 T702).......it should be 2.7v mono/0.5v stereo.
Another thing.....when I turn the unit OFF, I get some awful crackling in the earphones(only earphones at the moment...don't want to blow speakers)...what could cause this 'turn-OFF-crackling"?
Also...the MPX board is choke-full of 2sc458 's.(all except one 2sc870).........On the scat' it says all the tr's should be 2sc870 's............should I change those dreaded 2sc458 's?
Reg. The above info....I posted it in an older sx1000tw thread.......probably shouldn't have done that....sorry.
Could the crackling be a PS problem. I have just changed the caps...not the tr's. I don't have any of the recommended ztx695 or ztx795 tr's. Can other subs be used? Mje15032?
The stereo light does not come on(bulb is new). I have 21.4v on pin11 from PS....both sides of the r36 resistor have 21.4v(should be 23v/18v)......and the IND pin on MPX board has the same 21.4v. Is the resistor bad?
On c717 MPX board I have 5.5v(+ leg)....and when I tune away from stereo, I still get 5.5v.......so, I guess I there is something amiss. Sound out put is fine. Also r733 measures a constant 3.1v..(pin6 T702).......it should be 2.7v mono/0.5v stereo.
Another thing.....when I turn the unit OFF, I get some awful crackling in the earphones(only earphones at the moment...don't want to blow speakers)...what could cause this 'turn-OFF-crackling"?
Also...the MPX board is choke-full of 2sc458 's.(all except one 2sc870).........On the scat' it says all the tr's should be 2sc870 's............should I change those dreaded 2sc458 's?
Reg. The above info....I posted it in an older sx1000tw thread.......probably shouldn't have done that....sorry.
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