After looking at the schematic, I believe the speed is controlled by a quartz crystal. The main problem is getting the correct voltage setup for it. I'm not sure how that is done. There are parts that may be mislabeled, or I'm reading something wrong. A B&O dealer may be the best. I can't recommend anything, except the voltage does need to be corrected for 230 volts. Feeding that into it now would destroy it. Maybe someone with more knowledge on these, will come along yet. This is the first time I looked at the diagram on a B&O. Most TT's I use/used, have a synchronous motor. Those stay in sync with the 60 cycle (50 different countries) power from the outlet. The voltage could even vary about plus/minus 5%, without bothering the speed at all. The 60 cycles would have to be accurate( pretty accurate from utility ), and is accurate enough for a lot of people.