Inventors:
Leon F. Kolosko - Cheektowaga NY
Alvin S. Topolski - Tonawanda NY
Assignee:
The Wurlitzer Company - Chicago IL
International Classification:
G11B 2504
Abstract:
A two-speed automatic phonograph has a self-resetting, record-centering pilot to receive records having different size apertures therein. The records of different size apertures are to be operated at different playing speeds for reproduction of the sound tracks thereon. The speed at which the record is turned, i. e. 331/3 rpm or 45 rpm, is automatically controlled by sensing a characteristic of the record to be played. This will vary the frequency of a signal source which controls the speed of rotation of a synchronous motor which drives the record turntable at the proper playing speed. Also, the motor drive circuit includes means for applying a high voltage to the motor during startup thereof and for reducing the voltage applied to the motor during normal running while a record is being played.