Problems with stun gun.

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wangpushups
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Thu Nov 29, 2007 4:28 pm

It works but when i hold the trigger down it takes a while for the stun gun to warm up, and after about 30 sec. of me holding down the trigger it starts to work. Anyone else had this problem?
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psycix
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Thu Nov 29, 2007 4:47 pm

Maybe it has a capacitor that needs to be charged until it can work.
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paaiyan
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Thu Nov 29, 2007 4:56 pm

Psyc, of course it has a capacitor.

Capacitor isn't charging quickly initially. Low battery? I've never used a stun gun, but I would think that the battery may be low, causing the capacitor to charge slowly initially, but when the spark actually begins jumping, there's enough voltage coming back through that it charges quicker.
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Thu Nov 29, 2007 5:02 pm

It should throw a arc rite from the push of the butten. My circuit will knock you on your rear end quick. For sure try a new battery. If that don'0t do the trick, must be a bad connection somewhere.
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wangpushups
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Thu Nov 29, 2007 5:06 pm

It has a brand new recharchable 9 volt in there right now. I guess i could check my wire connections but i really think that its the stun gun itself.
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paaiyan
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Thu Nov 29, 2007 5:08 pm

WEll it's obviously not your capacitor (array?) seeing as it works good after that initial charge. Maybe you shoudl try a regular battery. Rechargeables are actually normally less than the normal voltage, that could be a problem maybe.
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wangpushups
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Thu Nov 29, 2007 5:13 pm

Really? I never thought of that. This one time i had a regular one in there and it worked way better than a rechargeable.
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paaiyan
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Thu Nov 29, 2007 5:15 pm

I know that I had some rechargeable AA batteries that were 1.1 volts instead of 1.5, I don't know about 9 volts though. It could be a problem, it may not be.
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wangpushups
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Thu Nov 29, 2007 5:20 pm

It's about 8.2 volts.
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Fri Nov 30, 2007 12:10 pm

When you say it doesn't work do you mean when wired to the spark gap in a gun or when operated in the way the stungun was designed?

Try using a smaller spark gap and see if it'll spark right away. Just attach a short piece of wire to one of the electrodes.

Stunguns aren't exactly precision instruments. What do you expect for less than $20? (Want to bet that the stunguns police use cost a heck of a lot more than $20 each?) They do crap out. They do loose the ability to spark the default gap, though they will often still spark across a smaller gap. They do fail completely.

They are not designed to be operated for more than 1 or 2 seconds out of several tens of seconds. Repeated firing, especially running'm for more than a second or so, will kill most cheap stunguns pretty quickly.

Wangpushups report of a "warm-up" period is the first example I've every heard of this failure mode.

Offhand, I would guess that it is not a capacitor or a main power transistor problem since both those components are usually pretty much either OK or completely dead. The problem may be that the internal trigger gap has been used so much that it is pitted and burned. That opens up the trigger gap and requires a higher voltage on the cap before it fires. It takes the charging circuit a while to get the main cap to a high enough voltage to arc across the trigger gap.
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sjog
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Sat Dec 01, 2007 7:57 pm

Stun circuits have been very disapointing for me.
Get 50 shots or less some times. Then take it all apart and get out the soldering iron. Some circuits are real simple, 4 wires.
I live in Mass. can't get the whole thing here, had friend in Vt. bring 2 down.
I took the cases off both( dumb ass me) and they were to complex for my liking. Should have used them whole!!??
Battery powered BBQ ignitors are easier to rig and are hard to kill.
A spark is a spark
Bat. ignitor does the same thing, performance wise.
www.ApplianceFactoryParts.com < BBQ ignitors
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singularity
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Sat Dec 01, 2007 8:51 pm

well there should be 3 basic parts to a stungun the primary coil, the secondary coil, and the switch. the switch creates a high frequency oscillating wave. the wave oscillates the the 9v from the battery which is fed into the primary coil, this coil bring the voltage up to around 300v. then there must a second switch which oscillates the 300v and puts it through what appears to be a iron cored coil (ie a mini ignition coil) this could easily generate tens of thousands of volts. if there were a capacitor it would be a filter cap to clean up the voltage coming from battery. it would not take more than a fraction a a second to fill. on top of that it would be very unlikely that it failed at 9V.

most likely not the capacitor, becuase there isn't one being used in the manner you are thinking of.

the second thing it might be is the battery. 8.4v is a bit low for a 9v in fact most of them are around 10v new. from my experiences stun guns are extremely sensitive to voltage changes i have a battery measured at 8.7v and another at 9.1v. when i use the 8.7v battery the gun's spark rate is cut in half. a low battery voltage could become a problem in two ways, it could lower the voltage of of the primary transformer witch would mean the secondary transformer doesn't have enough voltage to fire and there will be no spark. the second way is failure to trigger the gate on the switch. certain types of switches have very sensitive gates if the gate voltage is not achieved (within one volt in some circumstances) the switch will not turn on and the entire stun gun will be rendered useless.

so i would suggest going to the store and buying a standard 9v alkaline battery

i have two additional questions i need answered before i can go further into my analysis

1) does the stun gun still make its distinctive ticking noise even when its not actually sparking?

2)have you tried lessing the spark gap distance?
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Sat Dec 01, 2007 9:19 pm

rechargeable 9 volt batteries are capable of about 7.5v under load. its cause the reaction for the rechargeable battery produces 1.2 volts instead of 1.5!
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Sun Dec 02, 2007 12:33 pm

singularity wrote:well there should be 3 basic parts to a stungun the primary coil, the secondary coil, and the switch. the switch creates a high frequency oscillating wave. the wave oscillates the the 9v from the battery which is fed into the primary coil, this coil bring the voltage up to around 300v. then there must a second switch which oscillates the 300v and puts it through what appears to be a iron cored coil (ie a mini ignition coil) this could easily generate tens of thousands of volts. if there were a capacitor it would be a filter cap to clean up the voltage coming from battery. it would not take more than a fraction a a second to fill. on top of that it would be very unlikely that it failed at 9V.
Don't most stun guns use an internal spark gap as a switch to dump the ~300V in the primary cap into the second step-up transformer?

The internal spark gap usually looks like a pair of metal strips in an x-pattern with a very small gap between them.

The first stage of the stungun steps the voltage up to a couple hundred volts and stores that energy in the cap. When the voltage is high enough the internal gap sparks and the cap is discharged through the second step-up transformer creating the high voltage spark at the working electrodes.

Very small changes in the spacing of the internal gap will make the stungun not function correctly.[/img]
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Sun Dec 02, 2007 3:52 pm

jimmy101 wrote:
singularity wrote:well there should be 3 basic parts to a stungun the primary coil, the secondary coil, and the switch. the switch creates a high frequency oscillating wave. the wave oscillates the the 9v from the battery which is fed into the primary coil, this coil bring the voltage up to around 300v. then there must a second switch which oscillates the 300v and puts it through what appears to be a iron cored coil (ie a mini ignition coil) this could easily generate tens of thousands of volts. if there were a capacitor it would be a filter cap to clean up the voltage coming from battery. it would not take more than a fraction a a second to fill. on top of that it would be very unlikely that it failed at 9V.
Don't most stun guns use an internal spark gap as a switch to dump the ~300V in the primary cap into the second step-up transformer?

The internal spark gap usually looks like a pair of metal strips in an x-pattern with a very small gap between them.

The first stage of the stungun steps the voltage up to a couple hundred volts and stores that energy in the cap. When the voltage is high enough the internal gap sparks and the cap is discharged through the second step-up transformer creating the high voltage spark at the working electrodes.

Very small changes in the spacing of the internal gap will make the stungun not function correctly.[/img]
Yes, mine jumps a arc on the inside rite at the +. I don't know if thats wangpushups problem.
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