Hello all, I recently got a Sony PS-x600 turntable.
Everything works except it has a lot of WOW ( unstable rotation speed) - it is very audible.
I checked the speed with my phone, and I got an average reading of 33,33 which is ok but the speed oscilates a lot.
I got the service manual and checked the quick measuring points, one being the speed sensor and the values are in limit ( around 30mV). I cleaned the speed adjustment pots and got no improvement. I measured all the caps around the power supply section and they are like new, I measured the diodes around the power section and they also read good.
What I find strange is that there should be +30V and -30V supplied to the motor control board, but I read -27V and +26V with the motor off. The +15V and -15V rail both measure 14,6V so I guess those 2 are ok.
But if I run the motor the +30V rail drops to around +22V with fluctuation and -30V rail drops to around -25V also with fluctuations - which I'm guessing is not ok and could cause the speed issue?
Also is it possible to measure the motor windings if they are ok?
Any help or ideas would be very welcome!
Everything works except it has a lot of WOW ( unstable rotation speed) - it is very audible.
I checked the speed with my phone, and I got an average reading of 33,33 which is ok but the speed oscilates a lot.
I got the service manual and checked the quick measuring points, one being the speed sensor and the values are in limit ( around 30mV). I cleaned the speed adjustment pots and got no improvement. I measured all the caps around the power supply section and they are like new, I measured the diodes around the power section and they also read good.
What I find strange is that there should be +30V and -30V supplied to the motor control board, but I read -27V and +26V with the motor off. The +15V and -15V rail both measure 14,6V so I guess those 2 are ok.
But if I run the motor the +30V rail drops to around +22V with fluctuation and -30V rail drops to around -25V also with fluctuations - which I'm guessing is not ok and could cause the speed issue?
Also is it possible to measure the motor windings if they are ok?
Any help or ideas would be very welcome!