exactly. the ’x’ in the center of the knob turns.
the platter has dots on its bottom edge. the mirror with a light reflects the dots, they either move a bit, or, you turn the control, slowly, wait, don’t over do it. until they stop moving. now perfect: until the temperature changes, check every once in a while, maybe a refinement is needed, but as I say, you probably cannot hear the speck of less than perfect speed.
this minor speed change will happen no matter what power supply you use, which is why I say, don’t bother with one, just plug the beauty in.
my memory, far from perfect: the eddy brake is a shield. the shield is what moves as you turn the upper knob, effecting more or less magnetics to effect another part’s movement, to slow or speed things up. no contact, quite clever.
It’s a great turntable.
