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How do i make a capacitor charger circuit? Answered

I am talking about one for in a coilgun. i had a old (very old, 1.3mp) samsung digimax 101 digital camera, I decided that since i have moved on it was time to take it apart for the rich insides.

I knew what to look for, so i found it; the transformer for the capacitor charging circuit and the big cap for it. I unsoldered the transformer piece, cut the wires from the cap (it was not mounted on the board), and unsoldered the flash which had not 2 but 3 wires coming from it. one was yellow, one was green, and one was black and was attached to the deflector behind the flash. the black wire was connected to a small black piece that looked a lot like the charger transformer but only had two active pins instead of four. im not sure what it is for, i think it is a self resetting fuse, incase the camera short cicuits, but im not sure. any insight on that would also be helpful.

Back onto the subject, i would like to know what i need (other than the yellow transformer piece) to make the charger circuit. I have heard there was a transistor, would it be NPN or PNP?
there was also a diode, i am guessing one of the black ones, but is there anything else? i have those three things if that is all i need, but how do i solder it all together?

thanks in advance,

PS: the yellow transformer has only 4 pins that actually do anything, one is between two on one side and is only for support. either that or i accidentaly broke it.


I think you will find the circuits on this page
to be helpful.

I was going to say something about the foolishness of taking apart a perfectly good, working, circuit, you know... without taking, notes, pictures, making a diagram to show how to put it back together again... but I then decided that would be unkind. 

The link above will hopefully give you some clues as to how to put your charger circuit back together again, or how to build a new one.

ok, i just want to point out, like i told lemonie, the charger circuit was part of a larger board connected to a even larger board, it wasn't exactly an option to stuff the whole camera into the gun.

I will check out the links you both posted though.

no, it was part of the rest of the camera, and the 2 circuit boards had to be connected together in order for it to start the charge cicuit, and the boards were not exactly small, so i decided that it shouldn't be too hard to put it back together on a separate board.

so in short, it was on a big set of circuit boards that had to be hooked together to work.
i wanted it to be more smaller form-factor, so it would fit in the shell for my gun that i plan to use.

Yes, I know them. How to reconnect the bits is on the PCB - trace the copper-tracks and you'll know what goes where.


the only problem is that there are several little spots where the trace crosses over to the opposite side of the board, and some traces split two ways, and a couple go to a IC.

this is quite confusing!

i looked at the Coilgun handgun instructable, the one tha won a competition, and in one of the steps a circuit diagram is shown, using the circuit board at least.
im not sure what type of transistor is in that part though, i don't quite understand the circuit from the way that it is.

i might have to go to the local thrift store and find some film cameras, that way i can figure this out. luckily, they sell them a dime a dozen, there are millions there, but i cnt get there on a sunday.
if i could just find a schematic of just that part of the circuit, i could make this.

well i went to the thrift store and picked up two film cameras at $2 each, how to use the first ones charger is a mystery, but the second one has 2 pins that activate the charging process, i finally found them after i shocked myself on the cap lol.