Re: Triggered gap controller

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

Original poster: "James T by way of Terry Fritz <twftesla-at-qwest-dot-net>" <jamest2000-at-att-dot-net>



Tesla list wrote:

> Original poster: "Jason Johnson by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <hvjjohnson13-at-hotmail-dot-com>
>
>

SNIP

>  Most triggered gap work so far that is known
> to me is based on the "standard" light dimmer ign. coil circuit, which from
> the way I understand it runs at only 120 BPS.

One good reason to use the light dimmer is because the trig coil requires
AC on the primary. The dimmer
synces up and provides the AC.
 I realize you know that, my point is that to fire a trig coil at a higher
rate requires an AC supply with
a matching higher frequency, or a seperate power supply, like a high
voltage DC supply. In other words a
strobe light power supply. This has been mentioned before. The idea was to
use the strobe tube trig. coil
to fire the gap. It wouldn't be that much of a stretch to use a beefed up
circuit to pulse an auto
ignition coil.


>  460 BPS and it wants a higher breakrate, and I would like to be
> able to controll the on time of the gap (which is doable with triggered
> gaps). It would be nice if I coul get a circuit that at the top end would
> allow me to fire an ignition coil to the trigger 'trode up to a minimum of
> about 800hz and have variable "on" over most of the u-second range.

 Now the problem with the variable "on" time. The output of the trig coil
is not continious. It is AC,
even though the primary was triged with DC, it is a fast DC pulse and it
"looks like" AC to the trig coil
( mabey some Guru can help with this explanation). So the only was the
stretch or shorten the output pulse
width is to increase or decrease the discharge time of the capacitator
through the primary of the trig
coil. No to complex but you probably need some decent test gear.
 Yes it would be possible to create several closley spaced pulses that may
look like a stretched pulse to
the gap, but I don't know. There may be issues I'm not seeing right off.
 For me, I would start examining some strobe circuits and decide the best
way to trigger a auto coil with
that. If you need some schematics ect, i will send them or post to Terry's
site.
 Regards,
 James

>
>
> << Jason R. Johnson >>
> G-3 #1129
> The Geek Group
> http://www.thegeekgroup-dot-org/