Sony PS-LX520 Turntable Breakdown! 

+uxwbill thank you very much for your response! I will see what I can do with a variable autotransformer. Wanna get that thing back to work, because I like it very much. just in case: If you happen to open that turntable anytime in the future and you could measure that specs for me, I would appreciate that a lot!! ;-)

I'll hazard a guess that if the transistors are getting their turn on signal and not responding, that they've probably failed. I never had to dive into the actual platter motor driver on mine. Looking back on it now, I think the inrush limiters on mine were also bad, as the fuse did blow one more time. I've long since donated this turntable, but I think I might still have the service manual somewhere.

@@uxwbill on the board, there are 4 variable resistors. After looking at the service manual, and tracing the circuits, there were two things I noticed. Power at all the test points in the motor's driver & speed regulation was too high, and couldn't get past the first 2 vari-resistors. I cleaned and 'worked' them, but still the same. So I bypassed them and the table works perfect!... I've retraced the circuit to see why that works, and I don't know. All the voltages are now normal when the motor draws current. I don't want to say the vari-resistors are bad, because they're not (they do what they're designed to do) and I think their purpose is to even the pulses to the motor halves (bypassing one vari-resistor, the motor will work with a push-start, but can be easily stopped). Maybe they're to limit when the current gets higher at times??? Still makes no sense to me because it draws current from the same point, and that point gets the voltage it's supposed to be after the vari-resistors... whatever, it works now 😃

As far as I'm aware, any P-Mount cartridge will work. I used an Audio-Technica cartridge on mine. It was cheaper than getting a stylus for the cartridge it came with.

***** Thanks a lot! I'll definitely try that. Was it a standard belt you ordered? Any advice on replacing it would be really great!

The circuit protectors have long been discontinued and the only ones I ever found were extremely overpriced. Take a look at the inrush limiting circuit -- mine later proved not to be working after it blew another circuit protector. You could substitute a suitably rated fuse or if you're feeling brave/foolish, could just bypass the IC protector. I gave this turntable away some time ago, so I don't have it any longer.

+Tri-County Electronics They might have been new old stock, I really don't know. They tested good and the turntable still works flawlessly to this day, although I don't use it nearly as much as I once did.