Re: Sam's High-Energy Double Car Ignition Coil Driver... Update

to: Barry

Another slick way to reduce the secondary's kickback is to put a 25 or 50
watt, 5 to 30 Ohm resistor between the ground ball and the ground itself. 
This helps to clip the harsh secondary spikes both reducing RF radiation
and reducing those nasty kickbacks into the primary circuit.  We have also
experimented with small inductors in series with the resistors.


> From: Tesla List <tesla-at-pupman-dot-com>
> To: tesla-at-pupman-dot-com
> Subject: Re: Sam's High-Energy Double Car Ignition Coil Driver... Update
> Date: Sunday, January 03, 1999 12:33 PM
> Original Poster: "B**2" <bensonbd-at-erols-dot-com> 
> Hi Sam, All,
>     I use a 0.33uF capacitor in series with a 10 Ohm non inductive
> power resistor.  I put this in parallel with my SCR.  I also put a
> stack of about 20 1n4007 in parallel, antiparallel to the SCR.  The RC
> network eats the hf that would destroy the diode and SCR.  The diodes
> protect the SCR from reverse voltage.  They also provide energy
> savings by recharging the main capacitor with the charge left overs
> not eaten by the secondary.  These values have been arrived at by many
> expensive trials.
>     My SCR pulser uses an scr with no writing on it from the ham fest.
> I bought 2 SCR's and used the second one to find the voltage breakdown
> limit.  I tried several different diodes across the SCR to protect it
> from reverse voltages when the arc on the secondary of the ignition
> coil connects.  The RC snubber network was calculated and tweaked from
> the General Electric SCR manual.  My main capacitor is 10 uF. The
> power supply is 600 Volts at about 1 Ampere.  With dual cored ignition
> coils at about a few hundred Hz it gives a 6 inch arc in air.  The arc
> is similar to that of a potential transformer.  The noise is
> deafening.  The coils soften after about 15 minutes.  The SCR is cold
> to the touch.  The 1n4007 diodes are also cool to the touch.  The
> snubber resistor is a bit toasty but not too bad.
>     I have never discussed this circuit or my apparatus before because
> it is VERY DANGEROUS.  The output is pulsed DC.  Very Very Dangerous
> and extremely painful as well ,if you live.
> Barry
> Making sparks with alternative power sources
>   Sam Barros.