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    has anyone installed the new vta driver board for a mklv 4..

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    tpaul

    Posts : 1
    Join date : 2017-09-04
    Age : 58
    Location : metairie,la.

    has anyone installed the new vta driver board for a mklv 4..

    Post by tpaul on Sat Mar 24, 2018 7:42 am

    i installed the new board on my mk4s when i bring it up.1 of the 100uf caps gets hot..the other is cool to the touch..i checked my wiring the direcyions of my electrolytic caps ....changed out that cap but got the same results.....any ideas???
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    tubes4hifi
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    Join date : 2008-11-30

    Re: has anyone installed the new vta driver board for a mklv 4..

    Post by tubes4hifi on Sat Mar 24, 2018 12:31 pm

    are you asking about C17 or C18, or C14 or C16?    Have you measured the DC voltage at the problem area?   C17 & C18 are 100v caps where there should never be more than 70v.
    C14 & C16 are 420v caps where there should never be more than 350v.  (unless you are running the amp without any tubes in it, then you could have almost 500v, especially if you
    don't have the 6.8K resistor on the quad cap to reduce B+ to the driver board.)

      Current date/time is Thu Jul 19, 2018 9:24 pm