PIN 6 on output tubes & grid stop/screen resistor...

Discussion in 'Shock Brother's DIY Amps' started by 0 2339, Jun 12, 2019.

  1. 0 2339

    0 2339 TDPRI Member

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    hope i can make myself clear on this one:

    looking at terminal designations of output tubes (el34, 6l6...) pin 6 is not used. they also don't show up on most schematics.
    yet, when i look at layouts i always see them connected to ether pin4/screen grid or pin 5/control grid - and not only that, usually the resistor that is only shown connected to pin4/5 in the schematics is wired between pin4/5 & 6...
    can someone share some light on this?

    thanks
     
  2. danlad

    danlad Tele-Meister

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    Just a bit of point to point wiring. Mounting the resistor on the socket so its oscillation damping properties are a-ok.
     
  3. Greg_L

    Greg_L Tele-Holic

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    It's usually just a convenient anchor point for one leg of the screen resistor and screen supply wire..
     
  4. 0 2339

    0 2339 TDPRI Member

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    alright, that makes sense - thanks guys : )
     
  5. Wally

    Wally Telefied Ad Free Member

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    It is even more interesting to get off into some high fidelity amps and see how some designs use the ‘open’ pins on a rectifier. As with that pin 6 and pin 1 on a 6L6/6v6 tube in Fender amps, those unused socket points are used as terminal points for connections. These connections have nothing to do with the rectifier in these cases.
     
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