Lipoly to power flash bulb

[sloper steve]

How would you go about making a pushbutton that sets off a flash bulb from a lipoly?
Does it need to charge up some capacitor or can the lipoly just power it straight?

[vintage1]

Do you mean the old sort full of magnesium, or a xenon flash TUBE?

[sloper steve]

I'd like to use it on the new ones but have no idea what they are called?
From what I read about the old ones it requires a dangerous capacitor.

Is it still dangerous?

What components are required on todays digital cameras that seem to just use juice from the batteries and don't need to charge up anything?

[tim hooper]

.......... todays digital cameras that seem to just use juice from the batteries and don't need to charge up anything?

Steve,

I might be wrong, but I was under the impression that if you leave your camera on 'auto' then the flash capacitor gets charged as soon as you turn the camera on, regardless of whether the flashgun actually fires or not when you take the shot.

Choosing to disable the flash will prevent this charging, and will prolong the life of the batteries.

tim

[sloper steve]

So capacitors are still used to send a jolt to the flash bulb?
Is it called a reusable flash bulb? I'd like to order a few single ones from a surplus site but don't know what to search for.

All you need then is a capacitor and a flash bulb?

[zagisrule!]

No, you need an inverter to raise the voltage of your battery pack to at least 100V. The inverter output is rectified and used to charge the capacitor, which is then discharged through the flash tube, and the process re-started.

What you would be looking for is a "xenon flash tube." You can salvage the whole flash unit from a disposable camera (inverter, capacitor, flash tube, everything you need) with flash if you want....save some time perhaps?





-Matt

[simingx]

And you also need the trigger transformer to provide the multi-kV pulse to the tube to trigger the discharge.... for more interesting reading, go http://members.misty.com/don/ . :D

[HELModels]

I'm looking at a flash which came out of a 35mm disposable camera. I pulled the flash circuitry out after the film was unloaded. This circuit has a transformer, rectifying(????) diode, some resistors, transistor, and a HUGE 330V capacitor. I have no idea how many farads as it is not marked except for voltage tolerance. It also has some other unknown to me device.

I would bet that You could also rip one of these out of a 35mm type disposable, as I did long ago, and with any appropriate DC source, adapt it to your purposes.

Do be careful with LARGE Capacitiors and use all precautions.

Good Luck

[simingx]

Beware of the charge on the capacitor... it WILL hold the 300+ volts DC for quite a while! Do NOT discharge it by shorting, you'll damage it. Instead use something like a 100 ohm 1 watt resistor.

[vintage1]

you get a really nice belt of one of these too :D

Definitely the best idea - pirate a cheapo camera.

Are you trying to simulate a model nuclear exlosion or what?

[headless]

lol... used to make zappers out of those things back in school... hot glued the PCB and used it to charge the cap...zap poor fellows... lotta power in those things.