My turntable P/S had an issue (after 20 years storage) that required the replacement of some caps and regulators. I was able to find a more recent schematic for my voyd. Finding this schematic was very helpful. Very appreciative of someone posting it online. I still require to calibrate the output. Unfortunately, I have not located any instructions for this procedure. The turntable uses Papst motors, 901 3520 001. The motor has 24V stamped upon it. Would this be peak, RMS, or peak to peak? Should I be setting the output to be as close to this voltage as possible while connected to the turntable?
Thanks in advance.
Thanks in advance.
It seems to be an AC synchronous motor, 24V is RMS.
In general it is not necessary to give it the full voltage.
In general it is not necessary to give it the full voltage.
I would have thought that a change of regulators and capacitors should not affect the drive level presets.
Somewhere in the range 16-24Vac should be suitable. The lower the voltage to the motor, the less vibration (AKA wow & flutter) it will impart to the platter. The optimum value for a fixed drive voltage is the minimum voltage that will reliably start the turntable. Alternatively a circuit that drops the drive voltage a few seconds after start will give max startup torque whilst reducing vibration during run.
I would expect the drive voltages to the two coils should nominally be the same, but it is possible that one or other could be adjusted for minimum vibration with any given motor.
Somewhere in the range 16-24Vac should be suitable. The lower the voltage to the motor, the less vibration (AKA wow & flutter) it will impart to the platter. The optimum value for a fixed drive voltage is the minimum voltage that will reliably start the turntable. Alternatively a circuit that drops the drive voltage a few seconds after start will give max startup torque whilst reducing vibration during run.
I would expect the drive voltages to the two coils should nominally be the same, but it is possible that one or other could be adjusted for minimum vibration with any given motor.
The Papst motor is a delta connected 3 phase 'Aussenlaufer' motor, being fed by a single phase supply, where the second phase comes via the capacitor, with Kirchoff providing the third. This works OK, but could be much improved by using a genuine 3 phase supply.
DIY 4 Phase Sinewave Generator for Turntable Motor Drive
and
3 Phase Class D amp for DIY BLDC motor Drive
DIY 4 Phase Sinewave Generator for Turntable Motor Drive
and
3 Phase Class D amp for DIY BLDC motor Drive
Not sure about that. Papst's data sheet shows the 901-3520-001 as a 2 phase motor.
Oops, you're right. That's the first Aussenlaufer I've seen that wasn't a 3 phase 🙁
Probably still better if driven by a 2 phase supply.
Probably still better if driven by a 2 phase supply.
Vinyl Engine has this schematic for a two-phase Voyd power supply which looks like it's up to the task:
Thank you all. Yes, johnmath, that is the schematic which I used. This version is an updated schematic, slightly differing from my older P/S but close enough to allow me to figure out the flow of the signal. I will lower the output of the signals being generated to allow the TT to come up to speed but low enough to help minimize continual correction. Thank you, again.