Re: Fattening-up an HT spark

On Sat, 26 Nov 2005 19:03:02 -0500, Boris Mohar
<borism_-void-_@xxxxxxxxxxxx> wrote:

>On Sat, 26 Nov 2005 19:17:45 +0100, Paul Burridge
><pb@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
>
>>The electronic ignition system I've been developing (just for a bit of
>>excitement) is firing up in a timely fashion; the only downer is the
>>spark's a bit on the weak side. Is there any way of fattening-up a
>>spark from an HT coil driven by a switching IGFET so it's nice and
>>chubby and blue rather than skinny and sort of yellowish? I've got
>>some half-remembered concept about using a capacitor in series with
>>the coil that resonates with it in a Teslaesque fashion, but am
>>stumbling about in the dark here, quite frankly. Any suggestions,
>>chaps?
>>p.
>
> Like this? http://www.viatrack.ca/Misc/PLASMA.JPG
>
>The plug fires via a conventional ignition coil. Connected to it is a diode,
>inductor and a 10uF capacitor charged to about 600V The diode must hold off
>the HV from the ignition coil and carry the current from the capacitor. The
>inductor limits the current. The spark plug must not have a resistor inside.
>The picture is a photograph of a single shot. The gap wear is significant. I
>have not tried fancy electrode materials.
>
>
>
>
>Regards,
>
>Boris Mohar
>

Cripes! 1.8 Joules, as opposed to typical 65mJ... but a 65mJ CD
ignition WILL make a juicy spark... just not a plasma (which is why
your "gap wear is significant" ;-)

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.
.

Relevant Pages

  • Re: Fattening-up an HT spark
    ... >excitement) is firing up in a timely fashion; ... The plug fires via a conventional ignition coil. ...
    (sci.electronics.design)
  • Re: Fattening-up an HT spark
    ... >>excitement) is firing up in a timely fashion; ... >The plug fires via a conventional ignition coil. ... >the HV from the ignition coil and carry the current from the capacitor. ... >have not tried fancy electrode materials. ...
    (sci.electronics.design)
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