mains driven clock ?

[Mooly]

I don't know how braking would work tbh. The eddy current brake AFAIK works over a very small range. You could get speed control by driving the synchronous motor electronically of course. Suppose a mechanical coned pulley could give speed adjustment.

Dunno is the honest answer 🙂

 

[indianajo]

You could put both induction and synchronous windings in one motor housing, then brake it a little with a friction load. You could also have one powerful induction winding that almost always runs the same speed, but will slow down if you put a brake on it ( or mash a rubber drive pulley). The company that can claim some feature, the cheapest, wins the consumer reports best buy endorsement. Doesn't matter how stupidly they did it, unless it breaks before the report can be written.