Tube Amplifiers
zgamestoo asked:

and began to show the effect of the crown, what? wrong? The twin tubes running at 12kV and a 6 amp? King of the plate, a grid of 2 each amp? King. The evaluation of rf amplifier? 160kVA The new tube has little glow inside. The old pipe (failed) has the effect of coating on the outer corona.


3 Comments so far

  1. Edesigner on June 17, 2009 4:22 am

    Most Radio Frequency amps will Corona ..If the Metal cap at the top had been struck and your confusing corona with oxidizing you will know pretty soon,,,also on most of these octal bases the pin for the grid can be used for a tuner with a small fluorescent lamp close by ..add a trimmer say 10 pf to ground and adjust the output to max..if you have a watt-meter all the better…also people call this effect gassing…and its basically a loss of inert gass and on the grid you can see small sparks from time to time…Take another look,,,is it really exterior corona or interior gassing..Just some hints from the E…

  2. Numbat on June 19, 2009 8:04 am

    Hmmm. I suspect your corona might not be actually corona. Corona is an ion discharge.

    A type of electrical conduction that generally occurs at or near atmospheric pressure in gases. A relatively strong electric field is needed. External manifestations are the emission of light and a hissing sound. The particular characteristics of the discharge are determined by the shape of the electrodes, the polarity, the size of the gap, and the gas or gas mixture.

    Usually, this occurs at high voltage points on either transmission lines or sharp points on high voltage lines.

    If what you are looking at is a blue/pink glow inside the tube, it most likely is gassy. A hard blue glow can occur in high vacuum tubes. It is very rare to see corona inside the tube (which should be at high vacuum).

  3. billrussell42 on June 19, 2009 2:03 pm

    tell us what you mean by this in detail.

    If the tubes have a blue glow inside, they probably need to be replaced.

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