[LordCloud]

The trimpots are to fine-tune the speed, like using a strobe-disc to get the speed dead on. The probable answer to the motor voltage is 12 or 24 volt,,,,,or somewhere in-between. Doug's suggestion of a variable power supply sounds good. I see a low voltage plug in one of the photos. Is that plug part of the motor assembly,,,,,,is there a cord coming out of the motor with that plug on it?

This is kind of like going to the doctor's office and telling him you don't feel good, without any real hint of the situation, and he is suppose to figure out the problem. The photo's of the table are nice, but don't help the motor problem at all. Is there no way to go into the motor assembly, in search of some other clues?

Otherwise, take the tuff hop and get a variable output regulated power supply and start the motor up. Otherwise we'll be at this for ever. I'd start at 9 volts and see if it grinds, and if so, up the voltage. You will need a strobe disc and a fluorescent lamp (driven by a magnetic ballast, like a PL13 trouble light) to see and get the strobe effect. Then fiddling around with the voltage should produce a 33 1//3 rpm at steady speed. This should be done with the belt on the platter, ready to go. With the variable voltage power supply, you may not need to adjust the trimpots, tho they may offer an easier level of fine tuning.

Wayner

Sorry, I wish I had more info to give. I included the pics of the table because someone else had seen the two together and said that the motor looks like a SOTA motor, and I believe the table is a SOTA, although I don't see how they fit together as the motor is an inch or so taller than the table and SOTA motors normally fit into the cut out on the plinth.

The plug is part of the motor assembly and comes out of the bottom as well as another little cord, like a ground cord something. I'll open it up and see what I can see.

[Scott F.]

I'd be very weary about plugging a random voltage power supply into the motor without knowing exactly what it is.

From the looks of the layout (switches and trim pots), it looks similar to a controller for a Premotec motor.

You are going to have to pull the motor casing apart and get make and model numbers. Otherwise you risk burning up the controller or the motor.

No doubt you are worried about prying off the pulley and bending the shaft or trashing the bearings. The pulley is a press fit design. It comes off reasonably easily if you take your time and do it gently. It takes two flat blade screwdrivers and two small pieces of wood to remove these (unless you have a micro-pulley remover). Simpley place the two small pieces of wood 180 degrees across from each other on the motor housing near the pulley. These will be used as the fulcrum point of the lever. Then use the screwdrivers as levers and pry up the pulley being careful to apply the same pressure to each side. The pulley, with a little effort, will (or should) come right off.

When you go to reinstall the pulley, you must be gentle. What ever you do, DO NOT pound it back on with something heavy or worse yet a hammer. If you happen to have a vise with a wide set of jaws, that is the best way to press the pulley back onto the shaft. You need to apply even, constant force to the pulley so that it slides down the shaft back into place....hence the term "press fit".

I've swapped the string pulley out on my Opera motor several times for a belt drive pulley. Its quite simple. I can see where it might be a bit unnerving for someone who hasn't done it before, especially considering how expensive motors are. Just take your time, don't force things and make sure you apply even pressure taking it off and putting it back on and you should be fine.

Just to reiterate, you NEED the make and model number of the motor. Otherwise you are likely to kill the controller or the motor.

[doug s.]

there's no way a simple 9v battery, like what goes in smoke alarms, will harm this motor/controller, even if it is significantly less than 9v, which is not likely.  it would be a simple test that determines if the motor works at all.  from that point, w/a wariable dc power supply, such as rim & i prewiously mentioned, it would be wery easy and safe to slowly increase the woltage to get proper speed, (w/aid of a disc & strobe); again w/o harming the motor.

doug s.

[LordCloud]

Opened the motor up, and this is what I found; 'papst motor gs 3 09 9343809005 16-22v 50-400hz 21-32v=hk pn01731896

[viggen]

Maybe this will work.

http://www.acoustic-fun.com/catalog/product_info.php?products_id=73

I am sort of in the same predicament and am looking towards this guy.  I know my motor is DC though.

[Wayner]

Excellent! Now we are getting somewhere. So, it is not a DC motor after all, as the 50-400hz tells us that it's an AC motor. I guess I would pick a voltage like 18 volts, stick with the usual 60 cycle (assuming you are in the US?).

Now your kind of screwed as almost all variable output power supplies are DC. I think the motor runs at 1800 RPM, like, my Empire, which also uses a Pabst motor, but it's 120 volt. The pulley looks similar in size and of course, the belt goes on the outside of the rim of the platter. This is a weird hysteresis motor, similar to the synchronous motor, as it locks onto the cycle, rather then the voltage to maintain speed, and uses the high RPM to maintain torque, rather then multiple poles as a synchronous.

We may have to get some heads together on this one, but I think you may only need a transformer to convert from 120 volt to 18 volt. Parts express has a 160va 18 volt toroidal transformer for about $50, part number 122-610. This transformer would have to be put into a suitable enclosure, and have an on/off switch on the primary. You should also probably put a .01uf (1000 volt) capacitor across the switch to stop switch make/break noises. Since the transformer ratio is about 6.6 to 1 (120 to 18), 1 volt variance on the primary side would be about .15 volts on the secondary side, so a 5 volt drop on primary would be about .75 volts on the secondary side, still within limits of the motor's voltage range.

You other guys,,,Doug,,,who ever else, what say you?

Wayner

[LordCloud]

Took the motor to the local electronics gurus, took the top off again, ran some tests, plugged it in....nothing. They say they have what it takes to fix the motor, but I am the least handy guy I know. So it's a new motor for me.

[doug s.]

i disagree that it would be difficult to find a wariable ac power supply - wariacs are readily awailable on ebay, and other places.  but, as wayner says, changing the woltage won't change the motor speed, as that's derived from the 60hz frequency.  but, w/o knowing the diameter of the platter this motor is supposed to run, and w/o knowing how much wariance the trimpots afford its speed, i would be hesitant to fix the motor unless it could be done on the cheap.  you may end up getting to working, but not be able to properly adjust the speed.  might be worth the risk, tho, if the cost to repair is cheap.

if you want to go the new motor route, i recommend the origin-live dc motor kits; not sure what else there may be, that's reasonable.

doug s.

[LordCloud]

i disagree that it would be difficult to find a wariable ac power supply - wariacs are readily awailable on ebay, and other places.  but, as wayner says, changing the woltage won't change the motor speed, as that's derived from the 60hz frequency.  but, w/o knowing the diameter of the platter this motor is supposed to run, and w/o knowing how much wariance the trimpots afford its speed, i would be hesitant to fix the motor unless it could be done on the cheap.  you may end up getting to working, but not be able to properly adjust the speed.  might be worth the risk, tho, if the cost to repair is cheap.

if you want to go the new motor route, i recommend the origin-live dc motor kits; not sure what else there may be, that's reasonable.

doug s.

I'm thinking about this one to start, because it's pretty inexpensive.

http://cgi.ebay.com/Timaudio-DIY-Separate-Motor-for-Turntable-LP-Player_W0QQitemZ350288524853QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item518ed2b635