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RE: Hot Tubes (Was "Tubin

At 11:25 PM 2/12/97 -0700, you wrote:
>Subscriber: robert.michaels-at-online.sme-dot-org Wed Feb 12 23:13:44 1997
>Date: Thu, 13 Feb 1997 00:06:28 GMT
>From: Robert Michaels <robert.michaels-at-online.sme-dot-org>
>To: tesla-at-poodle.pupman-dot-com
>Subject: RE: Hot Tubes (Was "Tubin
>
>
>[ ... ]
>T>am able to get a wonderfully bizarre brush discharge of five inches.
>T>These babies are a sensitve lot though. Ok, so now for the qustions: How
>T>hot is to hot for the 803's? I can run them for about two minutes before
>T>they get to hot to touch, this is with a 2400 Volt -at-~500mA (actually not
>[ ...]
>
>T>David Trimmell
>
>
>
>        How hot do like it, baby?  Most transmitting-class vacuum
>        tubes can =at minimum= run all day with their plates dull red.
>
>        Some are designed to run with bright-orange-hot plates.
>        The general rule seems to be: if the plates are metal, then
>        stick with red-hot as a maximum.  If the plates are graphite,
>        then bright-orange is okay.   They can (and should) be air-
>        cooled (like with a fan) for max. life.   The higher power
>        tubes fit (and require) special ventilated sockets.
>
>        Hey -- these aren't transistors, you know.   They date from
>        an era when men were really men, and you could literally
>        warm your lunch on your electronic equipment.
>
>                                In a fever,
>
>                                Robert Michaels

Your Tell 'em Robert!!!  

And none are more manly than John Freau, the white plate/ white knuckle
champ!  I have always been amused at how John uses the absolute max ratings
on the spec sheet as a starting point for design.  Luckily John is a veteran
hamfester and buys up tubes like popcorn. (good thing too).  The secondary
electron emission from his 833 plates exceed that from many tube's
cathodes!!!!  John could use radiation warning labels on his gear because of
intense IR output from his systems.  Anyone can operate a tube on spec in a
Tesla coil, but it takes a manly guy like John to experiment with gathering
data on stressed tube lifetimes while also doing Tesla coil experiments.

We have captured a lot of this Freauian boldness on tape and his
incandescent plate mode oscillators are a real hoot!  The electron density
in the cathode/ plate space vacuum must approach that of a conductive jelly!
The plates are the targets in these oscillating electron accelerators.

A little humor is always held in high esteem amoung us Tesla types.
Actually John's timely admonition about not proceeding beyond dull red
paltes is not advice from someone who hasn't vaporized a few plates and sent
more tubes than you or I will ever own to an early grave.  Heed his words
unless you have lotsa' toobz layin' around!

Richard Hull, TCBOR 
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