Solid-state Capacitive Transformer!

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Jolyon Cox" <jolyon-at-vatercox.freeserve.co.uk> 

Dear List,
Last year I conducted an experiment using a very low powered solid-state 
assembly
(a 555 oscillator driving an air cored step-up transformer via a pulse 
transformer and  H-bridge from 30VDC supply) to power a "capacitive 
transformer" TC very similar, if not identical, to the circuit described by 
ACMQ on his webpage 
<http://www.coe.ufrj.br/~acmq/tesla/mres4ct.html>http://www.coe.ufrj.br/~acmq/tesla/mres4ct.html.

Taking the 800 turn secondary previously used in my spark-gap TC and 
connecting one end to ground with the other connected to a topload 
consisting of a small metal can

and twisting a bundle of telephone cable wires into a circle to act as an 
influence plane surrounding the "secondary" (actually the tertiary as this 
is a 3-coil system) supported on glass jars

and connecting the output of the air-cored transformer between the 
influence ring and the grounded end of the third coil, I found  that this 
system (inverted magnifier or "capacitive transformer") apparently gave 
better performance with regard to the production of high voltage than a 
conventional magnifier using the same components,  with performance 
improving with increasing proximity of the influence plane to the topload.

Judging from the distance from the topload at which an NE2 neon bulb or 
fluorescent tube can be lit without contact the system generates a very 
strong electric field

the voltage is sufficiently strong to ionise the argon inside a regular 
tungsten filament bulb and make it glow with a strong purple light
while the current is sufficiently strong to make the glass of light bulb 
uncomfortably hot in a very short time
and even to make the filament glow with a whitish incandescence!

The system somewhat better at producing corona -which is hot and intense, 
especially with regard to painted or enamelled metal surfaces (i.e the 
topload and the enamelled wire)  -  than for making sparks to bare 
metal-which it also does, except that these are shorter. suggesting perhaps 
that the high voltage is only available at relatively high impedance -due 
to the nature of the capacitive transformer, perhaps?

I hope to supply pictures in the not so distant future. Meanwhile, has 
anyone else experimented with the use of a solid-state driver to power a 
capacitive transformer or directly-coupled magnifier?
Is it likely there is actually some merit in using the capactive 
transformer -in fact an "inverted" magnifier- over a conventional magnifier 
as the output stage of a solid-state system, -or was the perceived 
"advantage" of higher voltage from the capacitive transformer as opposed to 
a  conventional magnifier in my experiment more likely to be due to a quirk 
of the solid-state driver?

Jolyon.