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Tube safety question

Discussion in 'Miscellaneous [BG]' started by friedtransistor, Mar 14, 2014.

  1. I have a marshall class v amp, and it has a couple ecc83 preamp tubes. I have been wanting to make a 12v tube overdrive, but just can't justify the price of a tube. So I want to just borrow one from my amp to test a circuit. Thing is, I don't know if the tubes themselves need discharged before they are safe. I know the caps need to be, but that is just a simple warmup-full volume blast-sustain-shut off. Reason I ask is because I know tv tubes need dischared, and just wondered if amp tubes have that same dielectric-absortion effect.

    And kudos to the one who can help me decode the mystic tube socket black magic... Er, numbering. I know 1 is on one side of the key, and 9 is on the other, but how are they numbered? a) Looking down onto the tube (glass end), or b) looking at it from the bottom (pin end)?
  2. Tubes do not store any energy. They can be handled as soon as they are cool enough to touch.

    Numbering is clockwise looking at the bottom of the tube, or the solder side of the socket, with 1 being the first to the right of the key or space.
  3. Thank you so much! This helps me a lot, now I can now not have to worry about hooking b+ to a filament. Or between two gates... Uh, bases... Grids! I meant grids! Also I don't have to fear having a disposable-Kodak moment if I touch the pins on a tube. Out of the amp, of course. Oh, that reminds me. One time a friend had a disposable camera, and took the film out to get it developed, and said the board was for the taking for the one who shocked himself on the cap. So I, not able to resist having the myriad of caps and transistors, decided to try it. So I know what hv feels like, and don't recommend it. Although the occasional spark is fun, I also know it can be quite dangerous (try changing your bedsheets on a dry winter day •_• ), hence why I am just now starting to get into making hv supplies, and even then I don't wander outside the realm of batteries, except for the occasional stepdown supply. Thank you, then, for giving me some confidence working on a tube amp.