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john bunsenburner

Tue Mar 31 2009, 07:03PM

Registered Member #1937 Joined: Sun Jan 25 2009, 12:28PM
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Posts: 53

I just aquired the cirrcuit from a camara and want to be careful inorder to not break it, can any of you help me out, i added pics below.

[Moderator Edit: Please crop pictures to 400px wide or less, or link to them instead of attaching them to your post.]

hotcrazyfruit

Tue Mar 31 2009, 08:06PM

banned on 5/26/2009
Registered Member #1877 Joined: Mon Dec 22 2008, 02:03AM
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it dpends what you want to do with it >_> you may as well keep everything connected just so you can charge it to its full potential. but you may want to ad an SCR to each terminal of the cap, so you can discharge it into things and make a coil gun xD
EDIT: crop your pictures next time. the mods will most likely lock a thread if they are 400x400 pixels. (i found out from experience)

john bunsenburner

Tue Mar 31 2009, 09:04PM

Registered Member #1937 Joined: Sun Jan 25 2009, 12:28PM
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Posts: 53

Ok, so what part is the boos converter? And what parts can i just leave out? I woudl liekt o just use that i need as the other stuff gets in the way also i will keep thsi simpele so not SCR.

Barry

Wed Apr 01 2009, 01:34PM

Registered Member #90 Joined: Thu Feb 09 2006, 02:44PM
Location: Seattle, Washington
Posts: 301

john bunsenburner wrote ...

Ok, so what part is the boos converter? And what parts can i just leave out? I woudl liekt o just use that i need as the other stuff gets in the way also i will keep thsi simpele so not SCR.

C'mon, learn to crop, learn to link from small images to big, learn to discard redundant pictures, and for pete's sake learn to use a spelling checker. If you don't bother to spend one extra second to type it better than a third grader, why should we bother to read it?

Smart questions

guitarlord66

Wed Apr 01 2009, 01:52PM

Registered Member #1805 Joined: Sat Nov 08 2008, 06:29AM
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I have used very similar camera circuits before,
I made a bank of 10 of them in parallel.

Once you solder a connection between those points when you apply power to the circuit it will charge, add a switch between the batter and the circuit.

One capacitor is going to be very weak... maybe shoot BB's with a small coilgun or something.

[Edit: Image size]

john bunsenburner

Wed Apr 01 2009, 03:23PM

Registered Member #1937 Joined: Sun Jan 25 2009, 12:28PM
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Posts: 53

Sorry about the typos barry, i made the post while in french class and so typed as fast as possible and did not proof read, and sorry about the pic sizes, any way i have the answer that i need, thank you.

EDIT: I did as i was told but it dd not help, there is still no electric flow around the capacitor, i spotted two points which might be the problem, maybe one of you can help me out(see pic)

Problematicareas

[Edit: Image size, edit the post to find out how the width tag works...]

Hon1nbo

Wed Apr 01 2009, 11:06PM

Registered Member #902 Joined: Sun Jul 15 2007, 08:17PM
Location: North Texas
Posts: 1040

the upper left circle is a default battery terminal, as for power not going to the capacitor, make sure the pads you soldered together are NOT the flash tube connections, if they are then you shorted the connections on your capacitor... the flash tube is designed to always be connected to the cap, even when not in use - these tubes use a Voltage lower than the breakdown voltage of the tube (what's needed to make it flash) then when firing use a small trigger transformer to set it off once the cap is charged, so there is no "switch" per-say on a camera board

as for the circle on the left, they appear to be the Shutter contacts for the flash... shorting those sets off the trigger transformer if the Cap is charged

EDIT: Also, a good and cheap, actually free, switch for a small coilgun, at least for a single charging board, is to leave the flash tube in place, but cut off one terminal, and then put between the points you just disconnected the leads going to the coil... then, to fire after charging by using the camera charging circuit, is to short the Trigger Transformer switch, i.e. the contacts in the right red circle you just posted...

Scavies430

Thu Apr 09 2009, 12:05PM

Registered Member #1924 Joined: Sun Jan 11 2009, 09:30PM
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Posts: 12

GuitarLord66 wrote ...

I have used very similar camera circuits before,
I made a bank of 10 of them in parallel.

Wait wait wait. Most capacitors in flash circuits are rated at 330V, and with one AA battery the capacitor voltage is 300V. Safety first! =(

guitarlord66

Thu Apr 09 2009, 12:26PM

Registered Member #1805 Joined: Sat Nov 08 2008, 06:29AM
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Posts: 67

Yeah there rated at 330v. you input 3v you charge twice as fast. I was really worried about overcharging at first but I've never had anything happen. They charge to around 340v and slowly rise, I mean slowly to max I've seen 370v and nothing happened.

Backyard Skunkworks

Thu Apr 09 2009, 07:41PM

Registered Member #1262 Joined: Fri Jan 25 2008, 05:22AM
Location: Maryland, USA
Posts: 451

You may not have had any catastrophic failures from overcharging yet, but trust me, it will happen.

Overcharging a capacitor past 120% of its rated voltage is generally a good recipie for an explosion in short order.

Using caps at 90% or less of their rated voltage makes a very long life.

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