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NE Ohio Teslathon/ Experimental 3 Phase triggered gap made for small coils



Original poster: "harvey norris by way of Terry Fritz <twftesla-at-qwest-dot-net>" <harvich-at-yahoo-dot-com>

3 phase triggered arc gap made for alternator tesla
coil

Much experimentation has taken place on the subject of
using a 3 phase triggered arc gap for a tesla coil.
The gap appears to function well, BUT I still have not
been able to get my secondary to show a top terminal
air born discharge. Several issues regarding polarity
issues for its operation led to changing the
arrangements twice. These will have to be dealt with
later on, as they involve quite a bit of explanation.
A breif explanation of this arc gap can be made here
without  going into the proper polarity issues, and
why by logic certain things had to be changed. This
apparently also led to a discovery about the proper
way to resonate spirals, something that did not become
immediately obvious, but if memory serves correct was
born out by proof of meter readings, but I will have
to refer back to those written notes later to
ascertain whether that proof was indicated by those
readings. Another longer document is in the works to
explain all these subsidiary issues.

As previously noted this concept involves using both
resonant interphasing (RI)AND resonant current
ballasting (RCB) of a 10 kva pole pig on the primary
side.
Reffering to the RI schematic;
http://groups.yahoo-dot-com/group/teslafy/files/RI/Dsc00260.jpg
the bottom resonance L4C4 becomes the predominant
amperage carrier, and is placed in magnetic opposition
to L3C3 and retuned in  that mutual inductance, to
create the highest midpoint voltage rise on L3C3. It
is this voltage rise that becomes the middle electrode
for the 3 phase triggered arc gap.

Then the quantity L4C4 is split into two sets of
spirals in mutual inductance with L3C3, so that this
can be used for a resonant current ballasting RCB of
the pole pig as shown at
http://groups.yahoo-dot-com/group/teslafy/files/MARX/DSC00093.JPG

The (supposed) fallacy of this approach, and the
corrections later made can be left as a useful mental
exercize for those able to see why certain corrections
to that approach had to be made, but irregardless
those corrections will be noted later in a more
lengthy posting. What becomes amuzing in making the
obvious corrections is that the interelatedness of all
aspects quickly becomes apparent. Essentially by
changing one thing, it does not immediately become
apparent on first glance how that action changes
another aspect.

It has been mentioned that the 41 nf capacity first
used in testings with an 30 ma NST had difficulty in
firing that gap. I was quite surprised to find that no
such limitations existed in firing the same capacity
with this 3 phase triggered arc gap. However since no
air born discharges have yet been made using this
method, (on my most primitive 14 gauge secondary
model), this actually means nothing at all.
I am now quite convinced that the small dimensions of
my primary on this coil has everything to do with this
problem, and now a scheme of typical Norris overkill
is in the plannings to correct the problem. I am sure
a great deal of laughter will be made when folks see
the substitute I will try to make for this primary.
The secondary with the NST firing at
Neon 8 inches above non arcing 1500 ft, 14 gauge TC
secondary, ( tuning near 1/4 wavelength) 
http://groups.yahoo-dot-com/group/teslafy/files/ATC/Dsc00267.jpg
became most unusual in the fact that when the
secondary was given a direct line connection to
primary, via Oudin method, then no neon action was
noted????
However with the 480 hz input via 3 phase triggered
arc gap, no neon action at all has been obtained,
unless the Oudin method was employed. The great no. of
tests using a large amount of differing capacities
made in this regard has become most discouraging, but
all these things should be approached in the spirit of
finding out the things that DONT work as a gradual
process of elimination. I am able to send at least 300
watts from the alternator into the process, and while
this is not a great deal of input energy, one would at
least think some kind of top terminal arcing should be
available with this input. Some of the secondary
windings have become switched around on the sonotube
secondary, so this is indeed not a perfect secondary
to be working with in the first place, and of course a
14 gauge secondary would also be very inefficient.
Perhaps the lateral placement, and relative vicinity
of metal  in the garage might be another issue for
making this failure to perform.
Neon Polar Capacity Bulb to TC secondary interior
volume for scope test 
http://groups.yahoo-dot-com/group/teslafy/files/ATC/Dsc00266.jpg
shows the small dimensions of this 10 gauge insulated
primary of black wire, which will be replaced by a
much larger version if this  construction becomes
feasible. 
Another theory and guideline for tuning is that the
placement of this neon polar capacity discharge in the
interior area of the secondary might actually be
stimulating a half wavelength responce on that scoped
secondary shown at
TC Secondary scoping by neon polar capacity/
alternator air core transfomer method/ 0.5 volts/div;
5 us/div 
http://groups.yahoo-dot-com/group/teslafy/files/ATC/Dsc00263.jpg
The consensus is that the 1500 ft  length secondary
with a 1.5/1 h/d ratio should resonate near twice the
111,000 hz found on scoping, but if this secondary is
responding at a half wavelength value, instead of 1/4,
this would explain the differences in the scoped
signal. Capacities employed for a 222,000 secondary
resonance with the 50 uH primary however have shown no
good results for any airborn arcing of top terminal.
3 phase triggered arc gap 
http://groups.yahoo-dot-com/group/teslafy/files/ATC/Dsc00269.jpg
shows the secondary top terminal connected to neon and
large toolbox as terminal top capacity. However since
this is also a Oudin connection of secondary to
primary, those results mean very little at all.  It is
hoped that someone can bring a small previously tuned
tesla coil to this years NE Ohio Teslathon, Saturday
Sept 7th, to try with these 480 hz inputs, to see if
there is actually any merit at all to these methods
employing a 3 phase triggered arc gap via 480 hz
alternator input. As mentioned my power input is
limited to 300 watts, but I would be glad to at least
see a 1 inch arc, rather than none at all, which is
what is being made at this time. The above gap was
made with ~ 15 volts input, consuming 6.8 amps on the
RCB made primary, with an additional amp recorded as
the stator line going to the top delta connection.
This is probably half the amount available from the
alternator for short runs without excessive heating
occuring on the alternator. Unfortunately during the
making of this jpeg, the voltage meter across L3C3
decided to quit working, so I am never buying another
meter from Radio Shack again without a warrantee, as
that voltage was well below the specified 750 volt AC
specs the meter is advertised for. Additionally I know
when NOT to use a meter by the signs of transients
that develope on its digital display. The amperage
reading on L3C3 was immediately disconnected when this
was noted, but no such problems on the voltage reading
had been noted. But I guess if ANY problems on a
branch were noted, ALL of the meters on that branch
should have been removed, so I will try to remember
this fact.
Sincerely HDN



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Tesla Research Group; Pioneering the Applications of Interphasal Resonances
http://groups.yahoo-dot-com/group/teslafy/

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