From: "Terrell W. Fritz"
Date: Thu, 16 May 2002 17:40:41 -0600
Subject: Re: [TSSP] Racing arcs
HI Boris,
At 01:17 PM 5/14/2002 -0700, you wrote:
>
>Paul,
>>
>> Results for k=0.20 at +20% and +50% primary tuning
>> are
>> posted up to
>>
>> http://www.abelian.demon.co.uk/tssp/pn040502/
>>
>> and I'm setting up the run now for the primary at
>> -20%,
>> -40%, and -60%, all at k=0.2
>>
>Great!
>First glance inspection and already
>:surprise,surprise!
>Pay atention to that +50% detuning anim.gif.
>"wilderness" :down-first 20% of coil lenght (base
>area) has about same voltage gradient like those when
>the thing is in a clear tune.If you have in mind that
>such voltage last longer than in resonant mode it's
>not odd that prim-secondary flashover can occur.
>Terry ,if I remember you mentioned one local coiler of
>yours had flashover accidents with that type of
>setting? Termed that like sort of "transformer"
>action?
>Well,call it the way you want but I'm going to call
>it:"Potato action" (according to nice voltage curve
>profile).
>Ehh..wild thing,you make my hart sing.
>
>Cheers,
>Boris
>
In my youth trying to build a Tesla coil, I tried a number of small
primary/secondaries that were more loosely coupled pulse transformers. No
tuning really just discharge a cap into a few turn primary with a many turns
secondary in the middle. My small little coil in a 7 inch diameter jar could
blow right through 3 inches of oil and the glass jar easily. Yes, the coupling
was low but the load impedance before the spark was very high so the voltage
shot right up. "i" think the same effect may account for racing arcs and the
very long (like) one foot primary to secondary arcs we see when a coil is out
of tune. This idea has never caught on with anyone but "me" but I figure with
all the work going on the truth either way will be found soon for sure.
"Potato action" is a little new to me ;-)) but anyway we can finally figure out
what causes the bazaar powerful arcs is fine with me :-) In Dave's coil, We
tried to insulate the primary and secondary and foot+ long arcs just went right
around the insulators. However, when the coil is in tune, you can't get it to
arc an inch... something very profound is going on there... I am still
stunned to watch this effect with all I know, and I really can't explain it
other than thinking back to my little transformer action coils.
If it does turn out to be a completely different effect, so be it. But if it
is transformer action, remember "I told ya so" :o)))
Cheers,
Terry
Maintainer Paul Nicholson, paul@abelian.demon.co.uk.