Re: Photoflash Caps

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

Original poster: "Jason by way of Terry Fritz <twftesla-at-qwest-dot-net>" <jasonp-at-btinternet-dot-com>

Jimbo,

I see what you want to do - drive an ignition coil!!! Right no problem, they
are frequently used here by people to trigger spark gaps, and generate high
voltage and low current.

Firstly, electrolytics are BAD for running ignition coils, due to the
ringing that causes the voltage output of the coil to rise so rapidly.
Generally, standard bipolar 'motor run capacitors' are used. They have a
high peak and high RMS outputs, and can take ringing without a hitch.
Charging up 100 or so uF of capacitor at 15 volts and dumping it through the
primary of the coil (whether mechanical or electrically switched) should not
be a problem, provided the right capacitor is used. If you want a suitible
capacitor, go for a low voltage AC motor start capacitor, and use that.

Good luck and keep us posted!

Best Regards,

Jason
[UK Geek #1139 Rank G-2]
[HV / Tesla / Laser / Comp]
[  www.thegeekgroup-dot-org   ]
----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Wednesday, September 11, 2002 3:33 AM
Subject: Re: Photoflash Caps


> Original poster: "JRW by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<jwhitmor-at-muscanet-dot-com>
>
> First of all, Thanks Jason. Lots of good information.
>
> The ringing that is so hard on electrolytics is exactly what I want to
happen.
> The circuit is something like the old {HYPERLINK
>
"<http://inventors.about-dot-com/library/inventors/blignition.htm>http://invent
> ors.about-dot-com/library/inventors/blignition.htm"}Charles Franklin Kettering
> electrical ignition system. Since an ignition "condensor" can last for
years,
> I may try something similar. I believe they were oiled or waxed paper
> dielectric,
> (probably polyester now).  If anything interesting happens I'll send an
update.
>
>
> Jimbo
>
>
>
>
>
>