marshall valvestate 8008 power transformer

Discussion in 'The Workbench' started by Andries, Dec 27, 2020.

  1. Andries

    Andries Member

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    hi i was wondering if the transformer in my 8008 is still ok because i measure
    30 volts between red and black wire from transformer
    30 volts between black and brown wire from tranny
    30 volts between red and brown wire from tranny

    shouldn,t there be 59 volts between the red and black wire

    schematic in the link below
     

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  2. Andries

    Andries Member

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    some pics
     

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  3. Andries

    Andries Member

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    pic
     

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  4. johan.b

    johan.b Well-Known Member

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    The two brown gets connected together on the pcb and then you get~60 volt red to black... why do you suspect the transformer?
     
  5. Andries

    Andries Member

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    hi i suspected the transformer cause i didnt measure 59 volts between red and black,but i figured out now that the brown wires are connected together and then i did measure 59 volts just like you wrote.
    thanks very much.


    so now i can start rebuilding ,new electrolytic filter caps ,new power transistors for channel a cause they were blown,new rectifier cause it was missing ,but first build a light bulb limiter ,so i wont blow all new parts when testing.
     

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