• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Lectron JH50 unknown parts?


I am trying to rebuild the board that provides a regulated 400V supply. This board is placed on top of the amp chassis next to the main power transformer and is usually not visible since it is covered by the large rectangular stainless cover with nameplate.

As you can see from the picture all the transistors have the names scraped off as well as that of the microchip. Does anyone know the part numbers for these components? I would appreciate any help or has anyone built an alternative regulator board.

Thank you.


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