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  • 811H problem, please read

    From Alan Beck@1:229/426.36 to ALL on Thursday, October 11, 2018 10:05:51

    Hi,

    I put a pair of 572B tubes in my AL-811 amp and they died.

    One went to a plate current of 600 ma and the other 75 ma.

    Anyways, DX engineering tubes are coming.

    I checked all my 572B tubes one at a time and selected the best I could for the
    amp. The worst case sceneria was 75 ma.

    Here goes.

    600 ma
    150 ma
    85 ma
    75 ma.

    Am I going to trash my amp or will the output just drop?

    It's holding at 500 watts right now. For 100 watts in.

    So, should I leave well enough alone or should I only the 2 tubes in there as soon as they arrive?

    If one fails short could that take my amp out?

    Best 73,
    Alan
    VY2XU

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