Accuphase A-48S


@imhififan 

Here are photos for rear of 3 boards you specified:

A-48S (7).JPG

A-48S (8).JPG

A-48S (9).JPG

I will appreciate very much if you would provide information on them.

Thank you in advance.

 

foolishman

Thank you. Makes sense. I was going off the specs on the NMD website which says that the transformer is a 3 pin input 4 pin output.

https://www.nmd-trans.co.jp/p2_PinTypePowerTransformaer.html

HTP-35-12 transformer.

Looks like there are a lot of transformers available that will fit this package format from various manufacturers with a good selection of output voltages.

I'll continue to use my amps with a step down transformer for the moment, but think I will have a look at converting to 230V sometime in the next few months as it sure would be more convenient.

Has anyone measured the output voltages from the transformer, do you know?

Cheers, Andy

@andyf 

Thank you for providing the transformer spec. Sorry, I don't know the output voltage of the transformer, maybe @foolishman  has measurements.

However, I remember there was a post from an old thread mentioned that the relay was a 18VDC relay, so I'm guessing the output voltage of the transformer is probably about 13.6 to 14V.

If you decide to convert the voltage to 230V, please post your findings and some pictures of the voltage conversion, I'm sure Audiogon forum members who want to do something similar will find your post helpful and appreciated.

I have some free time tonight, so let’s discuss some details on how to connect the transformer to 240V.

  1. Remove all the six transformer primary winding wires from the circuit board.
  2. Use a multimeter to perform a continuity test to confirm which wires belong to which primary winding.
  3. Connect the transformer primary winding wires as shown below.