Yet another about Stun Guns...

[TillEulenspiegel]

Well , you didn't rebutt what I said and I hope your statements are a reflection of a bad short term memory. Ad-Homs are not an argument. I won't waste anymore of my time argueing with a still as yet unformed mind. Evedently Nigel was correct in his responce.

/Ignore

 

[Nigel Goodwin]

To inform you I'm in Bjt's right now in my college which is about 4 or 5 chapters past Transformers and I got a 90% on my test for transformers so I'm afraid your wrong. And your rudeness is not needed so go play or cry to mommy or whatever little kid ok.

I've been keeping out of this, but only scoring 90% means you got 10% wrong! - I consider that a pretty low score!, I would have been seriously disappointed to fail 10% when I was at college!.

If you think you can get 240,000 watts from small batteries you are sadly deluded. I suggest you show the circuit and (mistyped) specifications to your teacher at college and ask them for their opinions.

I would also suggest that holding 30,000V at 8A in your hand would be rather suicidal - and if you were hoping to kill a bear from such a device, my money is on the bear :lol: not that we have bears in the UK!.

 

[TillEulenspiegel]

I would also suggest that holding 30,000V at 8A in your hand would be rather suicidal

BUT! I tell you what it sure sounds sexy. Small power source with huge outputs...Hmmm
I'm fairly sure it cannot be accomplished using current chemical reactions, but the prospect of high temp superconductor and buckyball lattices, coupled with new sub micron epitaxial depositing of conduction ,depletion areas "layercake style."...Interesting area.. Of course theres a finite limit due to molecular noise and tunneling . fascinating none the less.

 

[fat-tony]

Alright. Here's how it works.

There's two different laws in play here. I'm going to assume a 100% efficient transformer, just to make things easier.

You have a 10 ohm resistor. You put 10 volts across it, and get 1 amp. V=IR. Ohms law. You put 100 volts across it, you get 10 amps. Yes, voltage increases, current increases.

But, power in the system has to stay the same. If we have an output power of 1000W (100V * 10A) then we have to have an equal input power. Lets say we have a 10:1 step-up transformer. This gives us a 10V input and a 100V output.

For a 10V input to supply 1000W, we need I = 1000W/10V = 100A.

I hate to say it Painandsuffering, but you're wrong. P on both sides of a (ideal) transformer have to be the same. If it's not an ideal transformer, we need more input power than output power.

 

[DigiTan]

Ack! No one's answered my question about step-up transformers yet!

Where can one buy those miniturized step-up transformers like they use in the sticky shocker? I've tried a number of places like Newark already, but they don't seem to sell taser-type equipment.

 

[TillEulenspiegel]

goto you local drug store that has film developing ( Walgreen, Ekerd,etc.) and ask to by for $2 or so an empty disposable camera, you'll get a $5 lithium cell Hi AH, a 350V 100 uF cap a strobe lite and a transformer ........or just use the circuit as it is

 

[DigiTan]

Will this provide the HV discharge transformer or the feedback type? Also I noticed the discharge transformer from a stun gun I purchased a while back was coated in some type of adhesive-like clear fluid. Is this adhesive safe to handle? (Unlike capacitor oils?)

 

[TillEulenspiegel]

Ya safe It's just potted in resin to keep the coils from moving . Ever see a movie where someone is electrocuted? Where they jump around and contract? Well the sames to transformers when subject to HI V , they will coil and move like a spring.

Yes there are two x-formers the lo step up and the high output ...heck for $2 who can biatch ?

 

[DigiTan]

Cool! Okay, I just have one more question. Earlier I mentioned that I took apart my old stun gun. I had to do this because it will not fire at a usable rate anymore (usually 1 once a minute, if ever). It can still charge the storage capacitor (you can hear it too), but there is no voltage present across the probes.

I took apart the casing and discovered that the X-shaped spark gap was severely charred--probably from overuse. When I reapplied power I was able to manually set off the large arcs buy short-circuiting the X momentarily.

My guess is that the carred metal is preventing the spark gap from firing. How can repair the X-gap? Can it be done through cleaning or should I replace the whole X alltogether?

 

[Painandsuffering]

so smart

If you guys are so smart then how come you can't even realize that due to the build up the cap is holding before it discharges it is quite possible to have an 8 amp output. It has to do also with the transformer but the cap will up the amperage considerably upon discharge. And the bear wouldn't last against 8 amps. It wouldn't even take half of the output amperage to kill a bear but the question is who wants to get close enough to test it on the bear?

 

[Nigel Goodwin]

Re: so smart

If you guys are so smart then how come you can't even realize that due to the build up the cap is holding before it discharges it is quite possible to have an 8 amp output. It has to do also with the transformer but the cap will up the amperage considerably upon discharge. And the bear wouldn't last against 8 amps. It wouldn't even take half of the output amperage to kill a bear but the question is who wants to get close enough to test it on the bear?

You're dreaming! - it's simply a spelling mistake where you read it as you've already been told!. A capacitor can't provide more current out than you put in, it's basically a small storage battery - your batteries simply can't provide 240,000W to store in the capacitor (which would have to be absolutely huge!).

Feel free to try it against a bear - my money is on the bear :lol:

 

[Painandsuffering]

Nigel

Ok Nigel just to let you know I would win your money since I bear wouldn't be able to withstand 8amps. Not even a kodiak bear the Largest bear in the world would be able to withstand 8amps of current flowing through its heart. That bear would last about 5 seconds before it fell over dead then I could probably just chill there and eat him if I wanted to.

 

[grrr_arrghh]

Ok Nigel just to let you know I would win your money since I bear wouldn't be able to withstand 8amps

I think you missed the point. Nigel was saying that a the stun gun wouldn't give out 8A, so the bear would survive (obviously it woudn't if the gun really did give out 8A, but personnaly I believe Nigel and EVERYONE else in the post).

Learn to admit you are wrong. Just learn from it and move on.

 

[Nigel Goodwin]

I think you missed the point. Nigel was saying that a the stun gun wouldn't give out 8A, so the bear would survive (obviously it woudn't if the gun really did give out 8A, but personnaly I believe Nigel and EVERYONE else in the post).

Learn to admit you are wrong. Just learn from it and move on.

I think we should make him face the bear :lol:

If someone (if we can find someone stupid enough?) would like to video it and stream in on the web - we could all watch him die! (horribly!).

 

[DigiTan]

240,000 watts

Those must be some batteries! :?

 

[fat-tony]

240,000 watts

Those must be some batteries! :?

Well, let's assume that the battery is in a 100g Aluminum case, and that this 8amp discharge (240,000W) only lasts for half a second.

Specific heat of aluminum is 0.902 J/(g 'C) => 0.902 J/g'C * 100g = 90.2J/'C

240000W => 240000 J/s * 0.5s = 120000J.

120000J/90.2J/'C = 1330'C.

The battery holder would heat up 1330'C in half a second . Probably don't want to be holding on to it.

 

[TillEulenspiegel]

Give it to the bear.

 

[xenoxion]

Re: Nigel

Ok Nigel just to let you know I would win your money since I bear wouldn't be able to withstand 8amps. Not even a kodiak bear the Largest bear in the world would be able to withstand 8amps of current flowing through its heart. That bear would last about 5 seconds before it fell over dead then I could probably just chill there and eat him if I wanted to.

Even if you could produce the current you're talking about (which is next to impossible considering the size of stun guns), how would you apply it? Stun guns work by you touching the ends of it to a person close to you, so you'd have to get within a few inches of the bear without it mauling you to even use your stun gun.

Also, think about how much power you're talking about. Most 9v's are rated at around 150mA (so that's about 1.35 watts), and 30kv/8a is 240,000 watts. So, to even charge this thing, you'd need around 177,777 9 volt batteries! Not to mention the huge capacitor you'd have to carry around (a 300v cap is about 1/2 the size of a AA, and that's at very low current and capacitance, so a 30kv cap at 8 amps would probably be larger than your forearm.

 

[chemelec]

I wouldn't waste your time building this. It will never work to that high of voltage. Losses in the circuit Will Exceed Current outputs.

10 is About the most stages practical in this circuit and even that is doubtful.

Besides this is Nothing like a real Stun Gun.
Got to the Projects Area on my site for schematics of some Stun Guns.
**broken link removed**

Gary

 

[Crofty]

Re: oh

isnt 8 amps rather alot of current when the voltage is at many KVolts?i mean isnt that death type of current?

I think it's an obvious typing error, I suspect it should probably be 8uA.

I'm with Nigel on this one.. No way 8Amps @30Kv with every stage, the voltage increases, at the same time the current reduces.. so definately a typo.

Steve