I have this vintage device, it is a MOHA ME-300 MULTI VOLTAGE AC-DC ADAPTOR. It has multiple output connectors but I removed it and used it for something else. I tested the output but I do not get any, it seems to be broken but the Red LED still works.

The following are printed on the device:
MOHA ME-300 MULTI VOLTAGE AC-DC ADAPTOR
Input: AC 127/220V 50/60 Hz
Output: 1.5V/3V/4.5V/6V/9V/12V 300mA
MOHA in JAPAN

There is a polarity switch, you can invert the positive and negative output of the DC, another switch for the voltage setting.

The plug is of European but I doubt that it will fit, I need an adaptor, so I can use it in the Philippines. Near the plug, there is the last switch for input voltage, you can select either 100~127V or 220~240V.

This is an unregulated DC Power Supply, no safety fuse in the input and thin long wires on the output.

I have reverse engineered the PCB and tried my best to create a schematic using geda. You can download the Portable Document Format here:

REVENGR_ACDC_ADJ

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