You don't need to reinvent the wheel, just use what every team park use
to ignite gas, a standard and nice car 12V coil system.  The spark plug
is specifically designed to stand high temperatures and pressure, so you
don't even need to worry about the sparking device to be in the middle
of the fire or explosion, just extend the insulation to the middle of
the gas ignition point and use a traditional ignition system,
mecanically or electronically, switching 12V over the ignition coil.  To
increase the HV, just increase the voltage discharge over the coil. Lets
say you can store 130Vdc in a capacitor and discharge over the coil, you
will get a nice spark.  Just pay attention not to "fry" the coil with
overheat and burning the insulation.  Of course you should know all the
cautions to observe when dealing with propane, or explosion tanks, or
reserve a certain amount of gas inside a secondary tank before the
ignition, etc, etc. The most beautiful effect is submersed gas release
that burns over water along with dry ice smoke, some people use this
effect to simulate a volcano. Kids, don't do this at home.
Wagner.

RAYMOND WILLCOX wrote:
>
> Hi all:
>    I need a H.V. circuit design. The circuit must produce a spark in the
> range of 6 to 10 K.v. to ignite propane gas. Perhaps a camera flash
> schematic?
>    I intend to drive the H.V. circuit with a PIC by either pulling low a
> SCR, etc.. or continous oscillator and pull down sw. Any simple H.V. circuit
> you can supply will be greatly appreciated.
>    Thanks much in advance, Mark Willcox
> ________________________________________________________________________
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