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Thorens TD124 MKII - asking for help with voltage and line frequency adjustments

billinrio

New Member
Hello. This is my first post on this forum, so I should introduce myself. I have a quite large collection of LPs, principally of classical music, and over the years have accumulated an assortment of turntables, tonearms, cartridges, valve preamps amps, and speaker systems. I suppose that by this time most of this equipment may be considered to be "vintage", since its all from the 60's and 70's. Among my turntables are the Garrard 301 and 401 and the Thorens TD124, 125, 160, and 166. Recently, I moved from France to Brazil. In terms of electricity, that means I've gone from 220V/50HZ to 127V/60HZ. Thus, my question about the Thorens TD124 MKII, which I like to use in my main system, coupled with the Ortofon RMG 212 arm.

Although the machines are excellent, the Thorens manuals are far from models of clarity. The TD124 manual contains only a few lines in regard to adjusting the voltage setting. Since the line voltage here measures 127VAC, I moved the screw in the commutator to the "125-150 position. For line frequency, the manual claims that the table can be adapted for either 50HZ or 60HZ use, stating only that "... adjustment to the frequency of the power supply is made by reversing the motor pulley ...". It provides illustrations of the motor pulley in the 50HZ and 60HZ positions. Apparently, I need to remove two screws from the pulley in order to flip it over to the desired position. It also states, without further clarification: "IMPORTANT NOTICE. The motor pulley has been dynamically balanced to very close tolerances at the factory. When reassembling it, first tighten the black screw, and then the nickle plated one". Fine. I removed the screws. But the pulley doesn't budge. Removing the screws seems to make no difference at all. I don't want to force or pry anything, because in so doing I fear that I might damage the motor shaft. Its stuck. I'm stuck. I hope that some much more experienced forum member can provide guidance.
 
Hi there, the manual sounds quite clear on this really! The pulley should just pull off the motor shaft after you loosened the black and silver screw (you don't need to remove them) but after so much time it does usually stick a bit. Try pushing with the end of a ball point pen or something on the end of the motor shaft while pulling on the edges of the pulley. If that doesn't help, remove the belt and warm the pulley up with a hair dryer and try the same.
Mark
 
Thanks for the advice. It did finally come off. Its curious that Thorens deemed the tightening sequence of the black and nickle-plated set screws important enough to call attention to it in upper case letters. Do the set screws have different weights? They are so tiny, and I have no way to measure differences of a few milligrams.
 
No, its called precision engineering- the order in which they are tightened forces the pulley ever so slightly eccentric to the motor shaft. The pulley is balanced with them tightened in that order so the order should be repeated when re-tightening. They obviously thought it important- whether you'd hear an effect though...
 


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