Using Electric UK Gramophones in the US

[Zkeener323]

I've always liked some of HMV's electric gramophones but am weary to purchase one because of the voltage/Hz difference. I see many offer a simple wiring change to allow for the voltage. However, what about the Hz? On a synchronous motor, I would assume this would be problematic.

Does anyone have experience with this or know how to work around the Hz issue?

[Inigo]

If it goes with a special turret in the motor axis driving an idler wheel (the rubber one that rides on the turntable edge) then you need to extract the turret (usually a brass cylinder inserted on the motor axis) and grind (and polish) it to ⅚ of the original diameter, for a motor made for running at 50hz will run 6/5 faster at 60hz. You reduce the turret by this ratio and then the idler wheel will run on the turntable edge at the right speed.
I had the reverse thing done on an American Webster Chicago player to run correctly in Spain, at 50hz.
Save this caution, all will run perfectly (at the right voltage, be careful not to burn the circuits or the motor). If it has no way to change voltage, you can always plug in a small 110-120/220-230 AC transformer. I operate my Webster this way and it runs fabulous!
EDIT
This works with later record player models of the late forties, when the synchronous motor and the idler wheel became standard... of course my advice won't work on earlier electrical Gramophones with governor and mechanical gearing moving the spindle. Sorry.

[recordmaker]

The British mains supply voltage did not standardize until the late 1930s and most mechanical governor controlled motors have supply voltage terminals feeding different windings on the motor for 250 or 120 volts. this also allowed for export sales I assume.

[Inigo]

I edited my message for this correction, sorry

[Zkeener323]

Thank you all for the replies.
After further studying I have concluded the following.
If the motor is 50/60 Hz compatible then a simple voltage converter is needed, or as in many sets there is a provision to change the wiring to match the voltage

However, there are numerous 1930s record players produced from EMI/HMV/Columbia that utilize a motor that has the ability to change the voltage via altering the wiring in a simple manner on the apparatus- BUT the Hz isn’t changed. This would make a 50 Hz UK product have faster RPMs on a USA 60 Hz supply. Provided a governor is available. This could be rectified. Albeit, over prolonged use might cause overheating. But most units like this are synchronous. And do not have a governor. The best fix would be a frequency converter. But those are very expensive.

A cheaper fix is to first convert the US AC voltage to a DC current and then utilize a DC to AC converter that is specifically 220-240v 50Hz. The primary issue with this set up is there is added noise from the fans to cool the two units.

Of course if one were gifted enough. The worm gearing could be changed to have more teeth to possibly slow the motor down a bit.

I bit the bullet this afternoon and purchased a UK electric gramophone. I think I shall try to find a US motor replacement. I’d like a direct drive but given the small specifications of the cabinet of this HMV, I may have to settle for an idler wheel conversion as most US direct drive 78rpm motors are rather bulky for this shallow cabinet.

[Marco Gilardetti]

But most units like this are synchronous.

Are we really sure that these motors are synchronous? It never occurred to me in my whole life to come across a gramophone/phonograph turntable that really had a synchronous motor, and every time that I participated in a thread about turntables that were supposed to have a synchronous motor, in the end the motor turned out to be not synchronous.