You're correct. Jack had magnetofons. They used synchronous motors but
had a huge blower on the capstan motor to stabilize speed and cool the
spooling motors. A very interesting design.
Richard L. Hess wrote:
> At 02:08 AM 2009-11-04, Shai Drori wrote:
>> The solution is very simple. The capstan of the Tonschreiber did not
>> run off the incoming AC but had an oscillator and amplifier as a
>> servo. It could run at any speed from I think 9 to 130 cm/sec.
> Hello, Shai,
> That is true, but I don't think Jack Mullin's machines were the
> Tonschreiber model and were lacking the oscillator and amplifier, but
> also, I do not believe them to be true Hysteresis-Synchronous motors,
> The point here is that if Tonschreibers were used (or the circuitry
> associated with them was put into a studio recorder) then George's
> discussion of mains frequency would need another footnote.
> Richard L. Hess email: [log in to unmask]
> Aurora, Ontario, Canada (905) 713 6733 1-877-TAPE-FIX
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