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Discharge impedance questions.

Hi All,

	I got a bunch of questions about my recent experiments that I will combine
here into one post.

-----------------
"B2" <bensonbd-at-erols-dot-com> 

>Hi Terry,
>    Could you elaborate on the discharge length, appearance, and aural 
>qualities?
>
>
>Cheers,
>Barry
>

At 400 watts, it is about 5-6 inches long, maybe four inches in diameter,
fairly bright blue.  It sounds much like a typical propane torch used to
braze copper pipe.  I took chemical (those old style paper ;-)) pictures
that I hope develop ok.  The digital camera didn't due so well.  The Sony
VCR with night vision should do much better but I haven't tried it yet.
Maybe I can figure out how to hook it to the computer's video card to make
a movie ;-))

----------------------
"David Trimmell" <davidt-at-pond-dot-net> 

>Terry, all,
>
snip
>I know some feel Ozone and NOx are not so bad, but do not be caught off
>guard. I know that VTTC's (in both pulsed and CW mode) produce copious
>amounts of these noxious compounds (gotta love the smell, though), but
>perhaps the heat of the discharge helps to mix them with the air diluting it.

I will look into this more.  My disruptive coils produce far far greater
and overwhelming gasses without ventilation.  John has said his coils
produce lots of ozone but a later post (Ralph's) seems to suggest that some
coils do not???

----------------------
"Ruud de Graaf" <rdegraaf-at-daxis.nl> 


>Hi Terry,
>
>
>Thanks for the preliminary info!
>
>
>I'm afraid I don't understand the 'through about 10 feet of RG-8' part.
>Remember normally I speak dutch, so for us Europeans it's a little bit
>harder to understand the 'Tesla language'.

The generator is connected to the primary coil through a 10 foot long
length of type RG-8 coaxial cable.  A common 50 ohm transmitter cable used
for Ham radio and such.  Since I could tune the coil to almost no reflected
power, this cable should not have had any effect on anything.

>
>
>BTW, what I'am wondering about is the following: dV/dT is the most important
>thing in coiling, right? 

Well,  All kinds of things are important...

>When you quench the gap after one period to
>initiate the ringing in the secondary, would in that case it still be
>necessary to tune the primary on the resonance frequency as the secondary?
>You should think not, but my feeling says yes (I don't no why though). I'm
>talking here of course about a break-out situation.

There is no "gap".  The generator is connected directly to a primary coil
that is coupled to the secondary coil.  Apparently, the primary coil can be
a wide range of values.  The generator does all the frequency control and
the primary coil is only acting as a lossy transformer to couple the energy
into the secondary.  

I modeled all this in MicroSim before I hooked it up and the computer told
me such things would happen.  However, I didn't think it would tune to low
reflected power an I thought I would have to play with the primary
inductance more.  I was very surprised the computer was completely right...
 I should learn to trust it more ;-))

>
>
>Thanks in advance for the answer!
>
>
>Ruud
 
-----------------

"boris petkovic" <petkovic7-at-yahoo-dot-com> 

>Hi Terry,everyone, 
>Just a small input. 
>Interesting figures for resistances.As power and arc 
>lenghts go up you have more resistance.This is in 
>oposition to the case of usual TC operation where arc 
>resistance remains more- less same or even drops down 
>to some extent in larger systems as more power is 
>added.
>Regards, 
>Boris 
>

I think brush discharges have a different shape than the usual streamers
which makes the difference.  In this case, I also have prefect control over
the variables so the measurements are very accurate and everything is very
tame.  John and others have suggested that pulsing the coil will make the
streamers far different.  I will look into this.

-----------------
Parpp807-at-aol-dot-com 


>Hi John,
>This may be somewhat out of context:
>As Terry mentioned in his related posting, I have noticed that the wimpy 
>brush discharge
>from my type 10 VTTC does not produce ozone or any other ionization products, 
>at least 
>not detectable to the sniff test. Can you please comment on this?
>
>
>Happy day,
>Ralph Zekelman
>

Very interesting subject here!!  Some people's coil have ozone others do
not???  I have no idea why but perhaps the fancy RF generator's low
harmonic output is very "clean" of harmonics and non-symmetrical noise (I
think it is rated at -50dB).  Thus the positive and negative parts of the
AC cycle are identical.  If a tube coil's output were distorted and had
more (positive RMS current than negative or something like that), perhaps
that would promote creation of the ozone and nitrogen compounds??
Disruptive TCs like to arc in the negative potential much more than the
positive.  However a CW TC probably has pretty symmetrical currents - Just
a thought.

Cheers,

	Terry