RE: How long? (fwd)

["Tesla list" <tesla@xxxxxxxxxx>]

---------- Forwarded message ----------
Date: Mon, 06 Aug 2007 02:43:43 +0000
From: Jeff Behary <jeff_behary@xxxxxxxxxxx>
To: tesla@xxxxxxxxxx
Subject: RE: How long? (fwd)

Hi Tony,

Even tungsten gets too hot if there aren't any heat sinks.  If you can find 
mica condensers to run a coil ($$$ unfortunately) and use tungsten spark 
gaps with good heatsinks you can run them for extended periods, even up to 
an hour or more.

We have a few old forms of surgical Tesla Coils...

http://www.electrotherapymuseum.com/Manufacturers_Of_Electrotherapeutical_Apparatus/H.G.Fischer_Co/images/Fischer13.jpg
http://www.electrotherapymuseum.com/Manufacturers_Of_Electrotherapeutical_Apparatus/H.G.Fischer_Co/images/Fischer16.jpg

...that can run continuously.  The main thing for extended operation coils 
is to overkill the components a bit.  Use a larger transformer and operate 
it at less than full capacity; use a condenser with mica as a dielectric if 
possible - otherwise a modern oil-filled cap rated to a much higher voltage 
than that from the transformer.  For stationary spark gaps use tungsten rods 
but have them press fit or machined into copper or aluminum heatsinks:

http://www.electrotherapymuseum.com/Forgotten_Tesla_Technologies/Behary_Spark_Gaps/index.htm

For most TC components, overheating is the biggest issue...reduce this to a 
minimum and you're good to go for as long as you need.

Jeff Behary, c/o
The Turn Of The Century Electrotherapy Museum
http://www.electrotherapymuseum.com

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