Measuring Turntable Platter Speed

Your trying to measure WOW. A strobe test will tell you speed only..

Blow all the dust and crap out of the motor first.

Remove the belt and spin the platter. If you see the platter come to an abrupt halt after a spin you found your problem. If not it’s the motor and it need to be lubed and cleaned.  Make sure the bushings are not wore out and the armature is making contact with the field coils or to much end play. It’s only one or the other. The motor or the spindle. If the spindle well is full of crap, clean it out service the shaft and change the oil. It should spin for 100 years when it’s clean AND burr free.

OH WOW, NO WOW... Boo Boo.

Just a guess though.. :-)

IF you had the worst case of WOW (slow then fast then slow) the RPM might be affected. But it would have to be way off. No record today would cause it unless the the hole is punched off center. I haven't seen any or had any for a LONG time, unless it's on UTube. 

Motor, Spindle, Spindle Well, pullies and belt. There nothing else to cause it unless you actually have an electrical contact problem in the motor or powersupply etc.

I've seen it in fractile motors for rem drives TT.. Washing machine motors.

Russco/Sparta/QRK and the ity bitty Garrards.. :-)

Regards

IF you don't have the feel you can use a stethoscope and listen for the noise on the spindle pocket. You'll hear if something is wrong.. If you know what your feeling for you can just use your hands. Just have to pay attention..

Regards