Need to adjust the speed every time I turn on turntable

Sorry for a bit of nothing, but you wrote, "AC is not safer than DC - that was Edison’s argument...."  I interpreted that to mean that Edison argued that AC was safer than DC, which we both know was not the case.  I had a feeling you merely made an error in syntax, but I just wanted to get it straight. Now I see how you meant it.
Just think: If Edison had won the point, we wouldn't need rectification in our audio equipment, but on the other hand the DC voltages available for B+ would in many cases need boosting. Also, it would have been difficult to assure that everyone got the same DCV at home.

@lewm I see now that what I wrote was completely ambiguous!

If Edison had won the point, we wouldn’t need rectification in our audio equipment, but on the other hand the DC voltages available for B+ would in many cases need boosting.

We’d be in a different world if Edison had prevailed, for sure. For one thing, we’d probably be paying a whole lot more for electricity. I think the main reason AC prevailed is because of distribution efficiencies.

Oddly, solar electricity is DC. Edison would have liked that.

phoenixengr

Thank you for that insight around speed fluctuations, phoenixengr! 

In the later 90's, I had a full blown SOTA Star Sapphire with vacuum hold-down / electronic flywheel (line conditioner) - paired with a Fidelity Research fx64 arm with mid-priced Grados.  The speed would hold only through a 3-4 hour listening session no matter what I tried, including swapping out for a new motor with an engineer friend.   In the end, I simply lived with the issue.  Two decades later, it's still comforting to know that something can be done. 

During that experience, my rig was situated on a jouncy upstairs room, presenting a real challenge in isolating the turntable from footfalls, etc.  I tried bladders, masonry (never have had any luck with that,) tiptoes, sorbothane, etc...but, the "cure" in that application was a sandbox with super dry play-sand from hardware store and a carefully leveled maple plinth atop the sand under the SOTA.  Maybe this may help others. 

Happy listening and More Peace, Pinthrift   

A long time ago when I began to notice speed fluctuations on my VPI TT I cured it with a clean-out and lubrication of the bearing and a lubrication of the motor.  So that might be an issue,

But phoenixengr, who apparently now licenses his inventions to SOTA, solved the problem forever initially for me and other VPI owners with his Falcon/Eagle/Roadrunner.  Now sold together with a advanced design motor by SOTA.  If they make it in a way that is compatible with your TT you might look into it.  It's clearly the way to go for many reasons including better SQ, and it's quite low-cost for what you get.. 

Just wanted to point out that many of the posts seem to confuse long term speed stability with instantaneous speed stability.  A turntable may measure out perfectly for speed over longer time intervals yet still create momentary episodes of pitch instability due to short interval speed errors.  There's a difference.