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    New KT-120

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    Analogman

    Posts : 3
    Join date : 2010-03-19

    New KT-120

    Post by Analogman on Wed Mar 31, 2010 9:43 pm

    This is what Jim McShane has said about the info on the new KT-120's:

    Yep, and I must say the published data is not promising. First off, as you've already suggested, this tube doesn't look like it'll drop into much. Indeed - look at the heater current requirements. 1.7 to 1.95 amps per tube! That's 6% to 22% above a KT-88. Four of those could end up needing as much as an amp (or slightly higher) more than a four KT-88s. How well that plays with anybody's power trafo is to be seen I guess.

    The 50K grid circuit resistance is a big red flag to me. I agree with Wavebourn entirely.

    As well, after looking at the curves I'm not sure if a lot of amps are going to produce the bias voltage required. Note that the curves are almost all with a screen voltage of 250 volts or less. With 450 on the plate and screen it's going to want to pass a ton of current.

    Finally, if indeed the KT stands for kinkless tetrode somebody forgot to tell the designer. Those aren't my fantasy curves, to say the least.

    I'll try to keep an open mind, but color me unimpressed by what's on paper anyway.

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