LH1605CK based PSU - Not working

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  • michalismeim
    New Member
    • Jun 2017
    • 2
    • Greece

    #1

    LH1605CK based PSU - Not working

    Hello
    Newbie here, new to the forum as well!
    looking for your guidance on the subject below.

    I have bought an LH1605CK based PSU from a flea market.
    When I first checked it, it had a blown fuse and the transformer was bad.
    After I replaced the fuse and the transformer, I am able to get 30V at the output, but it is not adjustable.

    The design of the power supply is very similar to the example in the data sheet of LH1605CK, and all the components check ok.
    I am suspecting a bad ic, but since this is a discontinued model, I can't find a replacement to check. I found a piece online but it's way too expensive to worth ordering.

    so the question I would like to ask is if my assumption is correct, or is there anything else I can check that I am missing.
    I can post photos of the unit if you want, just let me know.

    I am trying to work out the schematic to post it here as well, but any ideas in the mean time are more than welcomed!!
    Thank you very much for your time!

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