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Can i drive a camera flash tube by connecting it to a capacitor directly? Answered

Can i drive a camera flash tube by connecting it to a capacitor directly .


All the professional tubes I've worked with "flash over" the tube with a trigger connection, where a breakdown of the gas inside is induced by a VERY high trigger voltage applied to the trigger pin. Steve


I just wanted to add that the trigger connection is somewhat mysterious in that it is often just a wire, or piece of metal, wrapped around part of glass strobe tube. The reason I call this mysterious is because it doesn't look like its electrically connected. How can it be considering the glass tube is an insulator? In truth, the trigger electrode is connected capacitively, but this can be a little confusing, especially if you run across just a bare strobe tube without a wire for the trigger input. You might find yourself wondering where to solder the wire for the trigger input.  Some pictures are attached, illustrating where the trigger input goes.


But i have a flash tube which has only two leads. how do i trigger it directly with a 300 v camera capacitor?

Sorry for the crappy formatting, but I can't get the "rich editor" to load today. The flash tube looks like it only has two leads, because the third "connection" for the trigger electrode is just a wire you wrap around the flash tube. The circuit diagrams shown on this page: http://www.talkingelectronics.com/projects/XenonFlasher/XenonFlasher.html should explain how the high voltage trigger pulse is produced via the trigger coil. In response to the questions: Where do I find these parts? Where do I find a trigger coil? The answer is that all this junk comes included with your disposable camera circuit board, and that's usually the cheapest way to go. Here's a link to the page of a surplus-monger who sells such things: http://www.goldmine-elec-products.com/prodinfo.asp?number=G16329 The disposable camera itself, probably cost a little more than this, before it was disposed of. The link where I found that first link: http://www.discovercircuits.com/P/photoflash.htm

No, they don't work like that (your other answers explain why better)


Not unless you have a very high voltage capacitor, and you charge it up to a very high voltage (which obviously has safety implications). A flash tube requires a very high voltage for a small amount of time.