Newsgroups: sci.electronics
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From: et@teal.csn.org (Eric H. Taylor)
Subject: Re: Electronic Tesla Coils
Message-ID: <C4s0G8.Dxv@csn.org>
Followup-To: sci.electronics
Summary: Real World Applications
Keywords: tesla, coil, osc, flyback, transformers, wireless, emi, ac, ignition
Sender: Eric H. Taylor
Nntp-Posting-Host: teal.csn.org
Organization: 4-L Laboratories
References: <1993Mar23.040116.14355@norfolk.vak12ed.edu> <C4CntG.Jv4@spk.hp.com> <1993Mar25.161909.8110@wuecl.wustl.edu>
Distribution: World
Date: Wed, 31 Mar 1993 23:12:07 GMT
Expires: Fri, 30 Apr 1993 06:00:00 GMT
Lines: 48

In article <1993Mar25.161909.8110@wuecl.wustl.edu> dp@cec1.wustl.edu (David Prutchi) writes:
>In article <C4CntG.Jv4@spk.hp.com> long@spk.hp.com (Jerry Long) writes:
>>Fred W. Culpepper (fculpepp@norfolk.vak12ed.edu) wrote:
>>[...]
>>A couple of years ago I put together a Tesla circuit which
>>was published in an electronics magazine and could have been
>>the circuit which is referred to here. This one used a
>>flyback transformer from a tv onto which you wound your own
>>primary windings. It also used 2 power transistors in a TO 3
>[...]
>10 years ago I built a 1'000,000 volt Tesla, and the thing was VERY
>spectacular, but besides scaring/amazing friends (depending on their
>knowledge of Science), and generating strong EMI, I never found anything
>useful that could be done with it ...  Is there any real-world application
>for Tesla coils today ?
>
>David Prutchi

First of all, realize that Tesla invented AC power generators, motors,
transformers, conductors, etc. Technically, *ALL* transformers are Tesla
coils.  In general though when someone refers to a Tesla coil, they mean
an "air core resonant transformer". The TV flyback version Tesla
coil (see the _Encyclopedia_of_Electronic_Circuits_ V3, 106-1 for
diagram) has NOT an air core. It is of a class of circuit called
"Oscillating Shuttle Circuit" (OSC). Generally OSC's are highly
efficient, but this version uses transistors and resistors,
which are very lossy devices. Typically Tesla used active
reactances instead of passive resistors, so that he could achieve
efficiencies of 99.5%, and better. The usual application of an air-core
resonant transformer, or of an OSC, is to produce strong EMI
for wireless broadcasts. How well do you think your computer
screen would work if we removed the HF HV Tesla (flyback) coil
from it? If we were to remove from our homes and industries all
Tesla coils, our lights would go dark, our cars would sputter
and die, our radios would go silent, our industries would grind
to a halt, and we would have to go back to using coal for heat,
gas for lamps, horses for transportation, steam for power, and
telegraph for communication. Is that real world enough for you???????

GET THE MESSAGE! WE WOULD NOT HAVE 1/100 THE CONVIENIENCES WE HAVE
TODAY IF NOT FOR TESLA. GIVE CREDIT WHERE CREDIT IS DUE!

If it had been up to Edison, we'd still be in the 19th century.
(flame me at your own peril. I'm very good at putting edison down).

----
 ET   "Tesla was 100 years ahead of his time. Perhaps now his time comes".
----
