Tesla project for the brave

[Xenophanes2]

Howdy all.While wading through the incredibly long 'Grey tube replication' thread on the 'other' forum I found a bit of gold that may have been overlooked in its million or so posts.This an interesting experiment gone wrong which may in fact provide what we are looking for.It is Mark Mackay,a.k.a. Spokane1,a highly respected member of the community,recalling events from the early 80s.Note this is an extraordinarily dangerous project that I wouldn`t touch with a 100' pole but I know some you may already have the apparatus and skill to make this happen.You also have to be a little crazy. Do so at your own risk!


"I was building a Tesla Coil in 1980 for a carnival Fun House following
the 1964Popular Electronics plans. It had a secondary 4" diameter x 48"
long. I was using a sheet of 1/4" plate glass from a pin ball machine
and aluminum foil as a capacitor. The NST was 15KV at 60mA. The primary
was about 28 turns of neon conductor around a 5 gal plastic bucket. The
spark gap was made from 4" galvanized box nailes (thin). I didn't have
any Terry filter, EMS, or other filtering. The base of the secondary
was connected to the case of the NST (Big Mistake). The spark gap
electrodes (the nails) were set parallel to each other about 1/2"
apart. The discharges were loud, intermittent and staccato like.
It operated for about 10 minutes before the NST blew. During that time
every metal object in the shop was emitting blue arcs to what ever
surface it could find. Tools on the shelf and on the counter were
arcing to each other. Even a nail that was in the plywood wall was
sending out spider web thin arcs that didn't connect to another object.
In the dark there were at least 100 blue arcs taking place all at the
same time at various places in the shop. Fortunately there were no
electronics at this same location.
At the time I figure this is what Tesla Coils do and decided against
making repairs since I was planning to use computer chip sound sources
in the Fun House as well. The Tesla Coil I thought would destroy these devices.
It was about 10 years later that I learned that this is not a common feature of Tesla Coil operation.
I still don't know what was going on there. I have been reluctant to
follow up due to the high price of NST's and the dangers of repeating the faulty connection to the case of the NST which is the center tap for the NST secondary.I have thought that the zinc electrodes had something to do with the anomalous action."

http://www.energeticforum.com/renewable-energy/3235-gray-tube-replication-92.html#post222549

Here is the 1964 popular mechanics issue he mentions.The only uncommon feature I can spot offhand is the glass plate capacitor.

http://www.scribd.com/doc/194978291/A-Tesla-Coil-Big-TC-Popular-Electronics-July-1964

Those of you familiar with "Secrets of Cold War Technology –. Project HAARP and Beyond" by Gerry Vassilatos will recognize the effect described.If you haven`t,here is a taste:

[Xenophanes2]

Here is the above mentioned 'Secrets of Cold War Technology',probably the most definitive work on Tesla`s experiments with so-called 'radiant energy'.You really need to read this amazing and sadly out of print book.

http://www.scribd.com/doc/41894231/Secrets-of-Cold-War-Technology

[Xenophanes2]

It also seems to me you could isolate the power supply (and thus keep it from melting),by using a Don Smith type coil pair as a buffer,utilizing. a center tap on L2 as opposed to the NST.Might keep it alive longer.Just a thought.

[TinselKoala]

I think anyone who has experimented with TCs has experienced what is described in the first post. This is an indication of a poorly tuned coil, actually. It's radiating so much broadband RF EM noise that everything in the environment capable of picking it up is doing so. A finely tuned coil is actually a pretty sharp RF transmitter and doesn't produce a lot of noise, either sound from the spark gap or in the RF as broadband radiated power. The power from a tuned coil will only affect tuned receivers (and objects that are coincidentally the right size and shape to resonate electrically at the coil's output frequency.)
The way to get a TC to behave properly is to reduce jitter in the spark gap. This means that a gap made of nails driven into a board is not going to be optimum. Beginning coilers think that a wide gap is necessary to make the voltage climb. This is not the case. A wide gap is hard to regulate and quench properly, and if there is enough voltage to jump the gap, there is probably also enough power to make a power arc. Even small primary voltages can produce large resonant rises in the secondary if the primary pulses are sharp and regular.
So rotary spark gaps in successful TCs are precision items and will generally use small separations in their actual sparking gaps. They also must be operated at the right speed to perform properly.
Protecting the power supply, with NST, is a matter of preventing voltage buildup within the transformer itself where it will arc over windings and short them out. This is done by providing a "safety gap" across the NST's output, which should be set so that it does fire once in a while when the coil is being operated. RF chokes  keep the coil's high frequency from flashing back into the NST. THe "Terry filter" design does the same thing, but is wasteful in terms of being a dissipative circuit. Normal HV chokes and a safety gap won't be constantly sucking power from your system like a TF will, but if you are using MOTs instead of NSTs (or in my present coil, TV flyback transformer) then you have power to waste so a proper TF might be a good idea in addition to a safety gap and RF chokes. The flyback doesn't have the power to waste though, and big NSTs are usually current-limited internally.

The Vassilatos text that you cite is describing a DC-output system, variations of Tesla's Disruptive Discharge apparatus. The ordinary Tesla Coil is an AC transmitter, so objects don't stay charged up when the coil isn't operating (they are being alternately positively and negatively charged during operation). The DC disruptive discharge coil would leave objects charged, as Vassilatos describes, like the DC field from a VanDeGraaff machine does. The "rays" that Tesla spoke of experiencing when he operated these systems were almost certainly mild X-rays given off from the powerful sparks generated by the disruptive discharge. Vassilatos has done perhaps more than any other single person to amplify the hype surrounding Tesla's work, his discoveries and what he may or may not have believed.