Vintage DD turntables. Are we living dangerously?

 Of course you can check each electrolytic for its integrity, before replacing it, and thereby save some cost and bother. But also you need not replace film capacitors. As a rule, they last virtually forever, if the unit has been stored at a reasonable temperature and humidity.  If you read elsewhere in this thread, you will see other problems that commonly arise especially with the solder joints and especially with the printed circuit boards used in the TT 101 which are known to be hygroscopic. And to be fragile.

But if you first replace the major electrolytic’s and see what you’ve got, then you can assess what other problems may apply. Also in my first post I neglected a very important point. Most TT101s were built for 100VAC. If you plugged yours into 120VAC that too might cause the failure mode you observed. You’ll need a step down transformer before you go further, if you haven’t already got one.

Look near the AC cord outlet to find the recommended AC voltage.

Yes, 120v 60hz 23W.

I used contact cleaner on each pot, moved them back and forth and set them back to where they were.
it did not take care of the problem.
the motor seems to speed up to top speed and then come down to almost a stop.
the digital display does not change because it seems that it’s taking an average.

There's simply no way the calibration survived that.  Barely nudging those pots drastically affects the circuit, and in the drive circuit they all interact.  The mechanically tolerance affects the setting, so aligning witness marks won't work.  Best rule of thumb on quartz/PLL DD circuits: don't touch the pots unless you can recalibrate yourself, or have it done. 

 Under the platter, you will find a rocker switch labeled “run” or “hold”. In the run mode the tachometer will display the RPM from zero to the set value. For example if you are set to 33.33, then the tachometer will read from 0 to 33.33 over and over again. This can be very distracting.  Maybe that’s what you are looking at. Check that switch under the platter. Set it to hold and you will see a static display of the RPM. At least you should see that. If you see anything else, that is an indicator of a problem. Also, I would point out, with all due respect, that cleaning the contacts is not tantamount to changing all the electrolytic capacitors. Without meaning to sound dour, the more you power up the unit without having identified the problem, the greater is the possibility that one of the hard to find ICs is suffering a fatal calamity.