UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Motor type

Kat Manton · 9th Oct 2010, 11:35 pm

An excerpt from the 930 schematic (the 927 and 930 are similar):

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As expected, it runs more smoothly (with more torque and less heat) when run from a 3-phase supply, 100V per phase, produced with three 100V-line power amplifiers, a multi-tap delay line and an audio oscillator set to just below 50 Hz. Hence I'm already designing a more compact 3-phase supply which will fit under the deck.

Some Empire turntables used a 3-phase motor (TT PSU article part 1 and part 2) too; the EMT isn't unique in that respect.

9th Oct 2010, 11:35 pm	#11
Kat Manton Retired Dormant Member Join Date: Jul 2005 Location: West Yorkshire, UK. Posts: 1,700	Re: Motor type - synchronous or not? An excerpt from the 930 schematic (the 927 and 930 are similar): As expected, it runs more smoothly (with more torque and less heat) when run from a 3-phase supply, 100V per phase, produced with three 100V-line power amplifiers, a multi-tap delay line and an audio oscillator set to just below 50 Hz. Hence I'm already designing a more compact 3-phase supply which will fit under the deck. Some Empire turntables used a 3-phase motor (TT PSU article part 1 and part 2) too; the EMT isn't unique in that respect.