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Re: A *Perfect* Tesla Coil



Subject:  Re: A *Perfect* Tesla Coil
  Date:   Thu, 17 Apr 1997 20:04:27 -0500
  From:   "Robert W. Stephens" <rwstephens-at-headwaters-dot-com>
    To:   Tesla List <tesla-at-pupman-dot-com>



> 
> >>snip
> << With both of us donning our 
> > silencing earphones I proceeded to crank up the power control variac 
> > quickly to the 35 amp position which corresponds to some 8 kVA.  Two 
> >odd things happened.  Firstly, I had to crank the variac higher than 
> > normal before the activity started.  I didn't really pay attention to 
> > this.  Secondly when the system did fire it came on with a loud shot 
> > gun report from the system cap safety gap.  As I instantly saw the 11
> > foot 
> > streamers between the towers and hot and heavy action everywhere as 
> > is now normal, I failed to notice that there was no familiar break
> > whine.  The 
> > system must have run for some 30-45 seconds and we were having a 
> > great old time watching a magnificent show when all of a sudden my 
> > rotary jumped to a big bright power arc.  It wasn't until this point 
> > that I noticed consciously that the rotary wheel was not spinning!
>  
> > I am absolutely amazed.  Here I had the rotary sitting still with 
> > what amounts to two gaps of about 3/8th of an inch (happenstance 
> > roulette wheel luck) with a vacuum 
> > cleaner blower forcing high speed air between the gaps through 
> > nozzles as is now a common part of my rotary designs.  This is in effect
> > a two
> > gap static quench gap!  The system was quenching just fine at 8 KVA 
> > from an 18,000 volt RMS pole pig type transformer!
> > This quenching was able to continue until the copper electrodes got 
> > so hot as to cause premature ignition of the gaps and it was game 
> > over for any quenching activity.
>  
> > I have NEVER witnessed a static gap of any kind, especially one with 
> > as few as two spark gaps in series, quench and operate superbly on a 
> > T.C. at anything anywhere near even 1/3rd of  8 kVA,... NEVER!
>  
> > My conclusion is that I have achieved synergy in its most advanced 
> > and most elusive state with this new Twin TC.
> >snip
> 
> 
> Robert, 
> 
> Congratulations!   As far as I know, this is something new for the Tesla
> record books.   Maybe twin TCs quench easier because there are two
> streaming
> toroids, impedance may be lower than in a single coil system?  Twins --
> the
> secret to quenching success?
> 
> > In coiling heaven,
> > rwstephens
>   >>
> 
> Towards optimal (twin) quenching,
> 
> John Freau
 
John,

Sorry for the long delay in replying to your post.  I'm running on 
dislexic time these daze.  Thank's for the complement.  I gotta say 
'back at'ya' for the great research you are now doing trying to come 
up with a handle on how system parameters affect gap quench.

This sucker sure is slippery isn't it? : )

As an aside which you will appreciate, I practically melted the top of
the paper
filled phenolic primary coil form holding the plate tank of my
Coronatron 
the other day from dielectric heating from extreme E-field.  I had a 
friend over operating the 35mm film camera for me so I could get a 
good shot of my 'Uncle Fester' stunt with an incandescent lamp in my 
mouth for posting to all our friends here on the list.  I let the 
Coronatron run for much longer than I had before (just idling at 2800 
watts RMS DC plate input) and went about my business walking around 
the lab picking up different lamps and doing different tricks.  I 
noticed a *smell* when I was near the machine and wasn't quite sure 
that it wasn't ME!  I have borrowed the secondary resonator from my 
MTC disruptive system and it is 15.5 inches O.D.  That puts it 
awfully close to the inside of the Coronatron tank coil form (about 
2.5 inch clearance all around).  The voltage on the secondary at the 1/4
way up
level is enough to smoke the phenolic with just isotropic space out
beyond the
phenolic form.  I'm building a maggy driver coil to immerse into the 
Coronatron tank coil to avoid this and other extreme field problems 
that will quickly beset any operator of this machine once I start 
dialling up the power to it's 15+ KW RMS output capability.  At 
merely this 2.8 kW input right now, I am generating a measured 185 kV 
P-P voltage sine wave at about 120 KHz with the present setup.  A 
small 3 inch diameter by 18 inch commercial spinning *just*prevents 
breakout to this point.  I get plasma globe fire inside a 1000 watt, 250
volt 
clear, mogul base filament lamp handheld at 8 feet from the machine!  
Approaching the coil with a grounded metal wand produces 24 inch long 
hissing St. Elmo's Fire.  If I stand on a wooden box with a crescent 
wrench in my hand about 3 feet distant from this coil and reach 
towards a person farther than me from the coil standing on the 
concrete floor of my lab with a similar handheld wrench we can get a 
very white hot, silent 2 inch flame arc between the wrenches that 
looks just like what you can draw from a 15KV-at-60 mA neon transformer!
There is absolutely NO nervous sensation.  I have a fully filtered DC 
supply driving my Coronatron and the 120 Hz ripple on the RF envelope 
is only about 5% at this power level.

Man, I sure hope my Uncle Fester pictures turn out.  You guys have 
gotta see this!

This aside almost just became another post! : )

Cheers,
rwstephens