Can I get a spark on demand?

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Fnord
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Wed Apr 25, 2007 3:12 pm

The easiest way would probably be to make a custom trigger.
Look at how a revolver works; when the trigger is pulled, the hammer is drawn back. When the trigger is at the farthest point back it can go, a spring is released and the hammer flies forward.
What you need to do is have the "hammer" in your trigger close a stun circuit when it is drawn back all the way.
you should get a very brief spark with a setup like this.

Maybe buy one of those crappy cap guns and mess around with it.
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paaiyan
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Wed Apr 25, 2007 3:32 pm

You could always just hold a couple wires and bang them together, lol.
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frankrede
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Wed Apr 25, 2007 5:31 pm

You are all being dumb and make this way to technical.
You need a timer switch.
end of story
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Fnord
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Wed Apr 25, 2007 6:23 pm

He orginaly asked for a spark each time the button was pressed, rather than at a set or timed interval. I was just trying to give advice for that.
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frankrede
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Wed Apr 25, 2007 6:56 pm

A timer switch could bused so that the stungun only runs for a certain amount of time each time the button is pressed.
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hi
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Wed Apr 25, 2007 7:11 pm

push the button really really fast, works for me.
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SilentJ20
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Wed Apr 25, 2007 8:19 pm

frankrede, they've actually been fairly constructive with their comment so far, and anyone trying to help me out is welcome. I'm trying to find a simple solution if I can. Has anyone set up a stun gun so that it charges the cap and then waits for a signal--button push--to let the spark go? I may research what the trigger is for a stun gun to create the main jolt. What cuts off the capacitor charge and releases it. I'm somewhat of a noob when it comes to electrical design, so go easy on me. And frankrede, your quote, "Nothing is impossible. If you can dream it, you can do it." I can dream it, I can visualize it, and I'm GOING to make it work :lol: Thanks for the help so far.
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frankrede
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Wed Apr 25, 2007 9:07 pm

My experience with stung guns is that there is no charging time, well a noticeable one in that case.
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SilentJ20
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Thu Apr 26, 2007 8:30 am

Did some research on this site:

http://www.emanator.demon.co.uk/bigclive/stunner.htm

Apparently the main shock is triggered by a smaller spark gap ( X shaped ) which then dumps the cap through a high voltage pulse transformer. I wonder if I can put a switch or relay on this initial spark gap to trigger the main cap dump, as long as the voltage doesn't build up too high. Anyone have any thoughts? I don't really want to destroy my only working stungun at this point.
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jimmy101
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Thu Apr 26, 2007 10:08 am

Use a 555 timer to control a stun gun. IIRC, stun guns spark twice per second or so. Use the 555 in an astable mode so it triggers the stun gun once every few seconds. Fairly easy to adjust both the on time of the stun gun and the time between firings.

Check Latke's page. I believe he has a 555 based timer that controls the on time of his chamber fan. Would be a starting point for making a repetitive circuit to fire your spark. See http://www.burntlatke.com/fan-controller.html.
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SilentJ20
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Tue May 01, 2007 3:29 pm

Da Pneu Kid wrote:You should install a capacitor with a lower capacitance rating.


Should have responded to this earlier. If I do this it will take less time to charge, but wouldn't it also produce a smaller--or shorter duration--spark? I guess that's not really a bad thing considering the massive spark they can put out normally. I may look into this, since a camera flash is already set up to go off at the push of a button. Should simplify things, since I'm not having any luck finding a 12V triggered relay capable of handling the potentially large voltages present in the trigger spark gap of a stun gun.
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GalFisk
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Thu May 03, 2007 6:56 am

you can use a SCR (aka thyristor) to precisely trigger a stun gun. One that will handle the voltage across the internal spark gap costs a couple of bucks at the most. It can also be controlled electronically.
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I posted some ideas on spudtech a while ago about self-venting combustion chamber designs, the images are not online anymore but if you're interested I can dig them up.
SilentJ20
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Thu May 03, 2007 8:07 am

GalFisk wrote:you can use a SCR (aka thyristor) to precisely trigger a stun gun. One that will handle the voltage across the internal spark gap costs a couple of bucks at the most. It can also be controlled electronically.
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I posted some ideas on spudtech a while ago about self-venting combustion chamber designs, the images are not online anymore but if you're interested I can dig them up.


I was hoping there would be a solution like that. Thanks for the advice. I'll look into the SCR's. For chamber venting, I think I have that covered, but I'm curious about your self-venting ideas. Didn't the images get saved into the SpudTech archive?
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GalFisk
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Thu May 03, 2007 8:14 am

Yes, I thought the images themselves were down since my site has been moved, but I see it has been at least partially fixed.
this is the forum thread: http://www.spudfiles.com/spudtech_archi ... hp?t=12401
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Thu May 03, 2007 1:09 pm

Hey GalFisk, I'm having trouble figuring out how I would wire up an SRC. My plan was to trigger it with a momentary switch to the SCR to trigger the spark, and I can't seem to find anything more than electrical theory on the SCR's and that's not too much help for me. Could you give me some pointers as far as hooking it all up? Thanks.
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