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Dedicated to the restoration and preservation of all original Dynaco tube audio equipment - Customer support for Tubes4hifi VTA tube amp and preamp kits and all Dynakitparts.com products


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    What are three three holes in the plates of a KT88 Tetrode for?

    alexbramford
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    alexbramford


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    • Post n°1

    What are three three holes in the plates of a KT88 Tetrode for? Empty What are three three holes in the plates of a KT88 Tetrode for?

    Post by alexbramford Sun Mar 12, 2023 11:41 pm

    What are three three holes in the plates of a KT88 Tetrode for? 2023-010

    Like it sez in the title: what are the three holes in the plates of a KT88 Tetrode for?
    What effect do they have on the electrical characteristics of the tube?

    These are the Svetlana Winged =C= (Black Label) KT88 output tubes in my VTA STA120


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    Alex Bramford
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    peterh
    peterh
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    • Post n°2

    What are three three holes in the plates of a KT88 Tetrode for? Empty Re: What are three three holes in the plates of a KT88 Tetrode for?

    Post by peterh Mon Mar 13, 2023 1:26 am

    I like to think they are for visibility of the grids, when manufacturing the grids should be
    aligned in order to have the g2 in the shadow of g1. It all boils down to creating a
    virtual cathode that suppresses electrons dislodged from the plate to reach the g2.

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    Tubes4ever
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    • Post n°3

    What are three three holes in the plates of a KT88 Tetrode for? Empty Re: What are three three holes in the plates of a KT88 Tetrode for?

    Post by Tubes4ever Mon Mar 13, 2023 3:24 pm

    As Peterh said, they are used during the manufacturing process for alignment purposes.

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    Seamus
    Seamus
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    • Post n°4

    What are three three holes in the plates of a KT88 Tetrode for? Empty Re: What are three three holes in the plates of a KT88 Tetrode for?

    Post by Seamus Tue Mar 28, 2023 10:55 am

    It ain't just KT88

    Look up power tubes on your favorite vendor site and most of them have plate holes.
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    • Post n°5

    What are three three holes in the plates of a KT88 Tetrode for? Empty Re: What are three three holes in the plates of a KT88 Tetrode for?

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