Jim Creek
Jazz, Wine, Electronics
After listening to my Pioneer PL41 for a while it became clear that the pitch was slightly higher than normal. I put a 60hz strobe disc on the platter. Shure enough, the table is running fast.
I checked the capstan. It has the groove that indicates it's for 60hz.
I'm not sure if it's the belt. I understand a thicker belt can make the platter run fast.
Then I found this post on Youtube:
"The problem is not a Mechanical one-do not waste working pulleys by filing them down-the reason that the Turntable is running too fast, apart from a slightly slack Drive belt through age is that the Load resistor in the rectifier panel to the Motor unit is tired and has gone "high", therefore, when these age, they start to carbon- break due to long-term heating effect of current over years and they start to "push" towards going open-circuit, but on the way there,they become tired and so the Voltage across them rises and hence the motor is pushed harder and runs fast. "
The PL41 uses an AC driven Hysteresis motor. There is no rectifier panel. However, there is a 300 ohm resister between the motor and transformer.
I am going to replace that resister, suspecting it may have gone "high" due to age.
What do you guys think?
I checked the capstan. It has the groove that indicates it's for 60hz.
I'm not sure if it's the belt. I understand a thicker belt can make the platter run fast.
Then I found this post on Youtube:
"The problem is not a Mechanical one-do not waste working pulleys by filing them down-the reason that the Turntable is running too fast, apart from a slightly slack Drive belt through age is that the Load resistor in the rectifier panel to the Motor unit is tired and has gone "high", therefore, when these age, they start to carbon- break due to long-term heating effect of current over years and they start to "push" towards going open-circuit, but on the way there,they become tired and so the Voltage across them rises and hence the motor is pushed harder and runs fast. "
The PL41 uses an AC driven Hysteresis motor. There is no rectifier panel. However, there is a 300 ohm resister between the motor and transformer.
I am going to replace that resister, suspecting it may have gone "high" due to age.
What do you guys think?