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Mystery electric phonograph motor

Posted: Mon Jan 31, 2022 11:20 pm
by streetmechanic14
Can anybody tell me what this might have been used for and how it might was connected? It may not be obvious in the pictures but there is a "phonic wheel" assembly under the induction disc. It is (as you might guess) massively heavy; the platter is cast iron. Note the size in comparison to a standard Victor motor of 1925-30 vintage.
-Dave

Re: Mystery electric phonograph motor

Posted: Tue Feb 01, 2022 12:06 pm
by Orchorsol
Possibly a Western Electric 203a according to this: https://worldradiohistory.com/hd2/IDX-A ... e-0050.pdf

Re: Mystery electric phonograph motor

Posted: Tue Feb 01, 2022 2:39 pm
by pallophotophone
It is absolutely from a Western Electric 203a non sync playback turntable set. ( I own one- somewhat incomplete) . Very sophisticated design- as were most of the electronic designs from Western Electric.
If I recall correctly, this motor uses a resonant AC circuit with condensers to control the speed. No mechanical means of speed control- all electronic.
The later WE non sync playback units used standard AC Victor-Universal- AC/DC brush type motors with mechanical governors.

It mounts to the bottom of the case. To access it, the turntable was removed, 2 thumbscrews loosened and the upper board hinges up. Supported by a lift lever. The later and much lighter Victor motor was mounted to the top board of each turntable side. There were complete 2 turntables/tonearm assemblies with a fader that would swing left or right to go between the 2 players. And a headphone jack - switch for cuing the discs.

I might have a schematic for it.

Nice Find !! Very Uncommon !!

Re: Mystery electric phonograph motor

Posted: Tue Feb 01, 2022 2:44 pm
by Orchorsol
pallophotophone wrote: Tue Feb 01, 2022 2:39 pm It is absolutely from a Western Electric 203a non sync playback turntable set. ( I own one- somewhat incomplete) . Very sophisticated design- as were most of the electronic designs from Western Electric.
If I recall correctly, this motor uses a resonant AC circuit with condensers to control the speed. No mechanical means of speed control- all electronic.
The later WE non sync playback units used standard AC Victor brush type motors with mechanical governors.

Nice find !!
That's something I'd absolutely love to own one day! But over here I'd need a 60Hz supply (funnily enough I was just corresponding with a friend about variable frequency mains supplies a moment ago). I can dream... :D But I do have a couple of 5A pickups, one with the shorter arm as on the 203a, the other with the longer arm as on the cinema soundtrack turntables.

Re: Mystery electric phonograph motor

Posted: Tue Feb 01, 2022 3:07 pm
by ChuckA
The motor is interesting in that it is actually a 3 phase motor. The capacitors on it are used to develop the other 2 phases when the motor is connected to a single phase source.

It is known as a slow speed synchronous motor it operates at a fixed RPM based on the number of teeth on the rotor, number of teeth on the stator pole pieces and frequency of the AC line.

Motor patent here:

https://pdfpiw.uspto.gov/.piw?PageNum=0 ... patimg.htm

Chuck

Re: Mystery electric phonograph motor

Posted: Tue Feb 01, 2022 3:18 pm
by pallophotophone
Seeing the schematic for it makes the operational parameters very obvious. Never would have guessed that the designer had that in mind.

Re: Mystery electric phonograph motor

Posted: Tue Feb 01, 2022 7:18 pm
by streetmechanic14
Thanks everybody for the information. I have one of the WE non-synchronous turntable sets but it's the later version using the Victor-style Universal motors and I didn't realize there was an earlier design.
Is the induction disc in circuit all the time or only at start-up (using some kind of trick on-off switch)? The only other phonic-wheel device I have is a Globe mechanical TV and, although like this turntable, a standard motor and phonic-wheel type are on the same shaft, the standard motor only supplies torque to start the scanning disc. After that, a front panel switch shifts power to the phonic wheel.
-Dave

Re: Mystery electric phonograph motor

Posted: Tue Feb 01, 2022 7:54 pm
by pallophotophone
Since there is no changeover switch or other method to control current flow, per se, it must be an integral part of the rotating armature/shaft.

Re: Mystery electric phonograph motor

Posted: Tue Feb 01, 2022 8:47 pm
by streetmechanic14
There is no change-over switch in what I have but then I have only the "raw" motor- nothing else. The patent info (Spencer; 1708334) shows a design using only the synchronous motor with no induction disc so obviously no switches are required. The switch on the TV I mentioned carefully prevents the use of both motors simultaneously.
Incidentally, I like your forum name "pallophotophone". Special field of interest? If so, I've got some questions!
-Dave

Re: Mystery electric phonograph motor

Posted: Tue Feb 01, 2022 9:55 pm
by pallophotophone
No- you have a complete motor. With out doubt. The only thing you are missing is the capacitor bank which is external to the motor. Each motor has its own bank. Located in another section of the wood case.

If I can answer anything related to General Electric Pallophotophone I'd be happy to. But a little history of how I discovered the name and its history.
In one of our best but long gone bookstores, I found a copy of "The Birth of the Talkies: From Edison To Jolson" authored by Harry M. Geduld. Published by Indiana University Press Copyright 1975
He briefly describes the process that is pallophotophone.
I was so taken by what General Electric was doing at that time, that I adopted the name Pallophotophone for my own. So far GE doesn't seem to care. Ha Ha Ha !!