Please, take a look at the attached photo.
The output is 24V AC; inside there is a little transformer.
You do not need 50Hz or 24VAC precisely; there are circuits within the gadgets that will do the needful.
Perhaps you have a strobe adjustment on the platter; if not read the manual on how to adjust the rpm...
solution:
From the local market, just get an wall adapter that gives 24VAC output (100mA is the typical current output and you need not worry much about the current rating)
In the worst case, you may have to take two 12VAC adapters and and combine the input in parallel and the output in series (you need to take care of the phase).
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Turntable often use synchnron motors.
Certainly correct; but using the power line frequency (via the adapter) to run the synchronous motor in a turntable is bad engineering.
However, I had a table clock that run on the power line frequency (but that was in the US) and it ran fine for years without losing a second (figuratively; I had no reference).
I expect a decent company to synthesize the frequency and even then I expect that there will be somewhere a pot to fine tune (the final speed of the turntable).
Most of the turntables are belt driven and the ratio is large (close to an hundred) and slippage is possible...