Disposable Camera Flash Circuit.

[Baske7Cas3]

Ok well... I am here again with an amazingly beginner question, but hey, thats what I am, so here goes.

I got a disposable camera flash charge circuit board which I am sure most you know creates a decent shock. Well, it is not an automatic flash charge which I am happy about but there is one little thing I need to change about it, I do not want to have to hit the actual button the circuit board because I will be setting this thing up in a case and it would not be very probably to have to find a way to push the metal thing on the bottom of it every time to charge the capacitor so I have come up with a little idea to be able to charge it from a switch so... I will try to explain a bit about the metal button that you need to push to charge the circuit.

Ok, so underneath the metal button is a circle that goes about 70% around and then there is a gap, the gap is there so that the metal circle that is inside this 70% circle has a way to get a connection through to the circuit without touching the 70% metal circle thing... if that makes sense. Moving on, this 70% circle has 3 metal plates attached to it, one on both ends and one in the middle. Well, how the metal switch worked is when you pressed it down it would create a connection between the 70% circle and the little circle in the middle, and this would then charge the capacitor. Though the metal button did create a connection between all three metal plates and the metal circle in the middle I don't think it is necessary to have to create a connection with all three plates since the 70% circle is all one piece of metal, I think it was just to make sure it got a solid connection.

Well, now let me explain my way... this is a very easy concept. I want to attach two wires (one to the 70% circle and one to the circle in the middle) I then want to run both wires to a spring switch with two prongs so I can attach each wire to a prong. That way, when I hold down the switch it makes the connection between the two, and when I release it it leaves me with a charged capacitor... I honestly have no clue if this will work but it was the only way I could think of to be able to make a switch that does not have to be attached to the circuit board.

Below is a picture that I made to help explain my idea.

**broken link removed**

I believe it will work but could someone please leave their own feedback on the idea?

And, if I do have to make a connection from all three metal plates (which I really don't think I have to, but maybe) then I can just have a wire from each one run to the same prong and then have the wire from the center circle run to the other prong.

 

[things]

just check if the circuit board is double sided, it seems a bit strange that they put 3 terminals when the only need 1????? try it, it can't hurt it,

 

[Baske7Cas3]

No, the circuit is not double sided... and also, how it works is on the circuit... there is dark green all around the 70% circle thing and then there is a light green strip underneath the metal that is connecting the 3 metal plates, so there is no circuit running from anywhere else except from the end of the 70% circle unless of course current runs through the dark green part to, but I didn't think so.

Also, they might have done it like that because the metal button that you push is like a triangle and each rounded corner was over a metal plate and there are little bumps on each corner where it hits the metal plates at... and then in the center of it, of there is another bump for the center metal plate... and it works like when you push it down and hold it, it will stay in place, but when you stop pressing it, it pops back up, so I think that the little bumps are to give it enough height so someone can push it down and let it have that popping action when you let go. And it appears that instead of having the bumps sit on the dark green of the circuit board they just put metal plates underneath them. The only thing I can think of is so the metal does not come in contact with the circuit board in any other way than it is meant to, or maybe so they are sure to have a solid connection.

 

[Baske7Cas3]

This is what the circuit board looks like... So, if you see a reason for all three please tell me, and it is not double sided (well it is but there are no running circuits on the other side, just the components). As you can see it resembles my drawing pretty well lol.

P.S. This is with the metal push button off.

**broken link removed**

 

[things]

yep, just switch the inner and outer tracks together, like in your drawing, it sholud work.

 

[Baske7Cas3]

Ok thx a lot, I just wanted your guys' opinion before I did anything stupid and ruined the circuit... and before I do it I guess I have a question or two.

1. When I put down the wire on the 70% circle thing can it touch the dark green on the circuit board. And I guess I will have to do a small piece of wire for the center one...

2. I bought a holder case for a AA battery, so can I just put the battering the case and then attach the positive and negative wires to the positive and negative battery holder on the circuit?

And if there is anything else you should let me know before I do this then please let me know.

 

[things]

yes you can just solder the battery holders leads to where the original ones went. and for your 1st question, just solder a piece of insulated wire onto the the middle pad, and one onto the outside "ring"

 

[Baske7Cas3]

Ok thank you again for all your help. lol I have yet to try this shock thing on me though, how does it feel?

 

[things]

i have not purposly tried shocking myself with a camera flash, but when i pulled one apart, the capacitor got me. it did hurt, but not too bad. just don't shock yourself across the heart in any way

 

[Baske7Cas3]

Well, lets say I think it is extremely weak in what way would I go about making it stronger? I am not saying I am going to lol, but I am actually really curious as to how I could make it stronger.

 

[things]

add another capacitor!!! but it would take longer to charge. try it out first before you add a cap though

 

[Baske7Cas3]

What do you mean it would take to long to charge? I don't care how long it would take lol... And I was wondering how i would go about adding another capacitor anyways? And if i did get another capacitor hooked up correctly, doesn't the circuit regulate the amount of charge, so wouldn't i basically charge up two capacitors to 50%?

 

[things]

just hook the other capacitor onto the original one, positive to positive, negative to negative. if you wire them in parallel (the way i suggested), you would get more current, and a bigger shock. but the camera circuit will take twice as long to charge the 2 capacitors, it will charge both of them to the same level though.

 

[Baske7Cas3]

ok... Cuz when I first thought about charging them, I thought to hook them up in parallel to, but I figured the circuit only put out enough charge to charge one capacitor fully...In other words I thought it was set up to only charge a certain amount but it is set up to charge until it gets a "notice" that it has charged the capacitor(s) fully? And also, when it is charging and it makes that cool "charging" sound... what is actually making the sound?

 

[things]

the high pitch "charging" sound is the transformer, the circuit sends pulses of electricity into the transformer, but the pulses are fast enough that you can hear them in the transformer windings. yep, the circuit won't stop charging the capacitors until they reach the charge they are set for, no matter how many caps you have

 

[Baske7Cas3]

Hmmm... the possibilities... lol... hey, where did you get your flyback from? and why are they called that anyways? and just to get this straight... tomorrow im gonna go ahead and try my idea on the switch to charge the capacitors, but i am also going to have a switch to release them, so to do this i need another switch which i have and all i need to do is attach two wires to each capacitor (one on both side +,-) and have both from one side running to whatever i am going to have people touch to get shocked and then i will have the other two going to the push button switch both on one prong... and then have a wire from the other prong going to the other bar or whatever that they need to touch correct? Which leads me too a couple more questions...

1. Will it be safe for someone to have a bar in each hand and have the charge go through the body with one capacitor? and how about two?

2. And i am assuming it would be safe to have both charge go in one hand so it does not go through the body, but i just want to ask anyways.

 

[things]

i got my flyback from a computer monitor, you can get them from anything with a crt tube. one capacitor should be alright, but i'd start to worry after that they are called a flyback because the thing operates by the voltage flying back to switch it off. if you mean just through the hand, it should be right. got to go to bed now, school tommorow see ya later

 

[Baske7Cas3]

ya... two would probably be to strong lol, but for those crazy people i will just put it in there with an on/off switch. hey Thx for all your help again and tomorrow when you get on I will probably have a lot more questions for you lol.

 

[audioguru]

If you don't use a current-limiting resistor in series with the capacitor and one of the prods, then your shock might kill somebody or cause something to catch on fire.

 

[things]

yeah, that's why i said to not shock people, where the shock has to go throught the heart. And only add 1 more capacitor if it doesn't hurt much, any more and you'd probably be in danger