Camera capacitor question:?
I've seen a lot of videos on youtube about disposable camera "tasers" where it takes time to charge up the device. I know that DC voltages don't work when using transformers to get the electricity up to 300 volts. Does the camera use a pulsed DC current? Also capacitors discharge immediately, so do they put in a resistor for the minus terminal of the capacitor so that electricity has a harder time flowing out of the capacitor than in from the pulsed DC current so the charge builds up? Is that possible?
More Questions From This User See All
Answers & Comments
Verified answer
You are correct in saying that transformers will not work on DC.
I think the capacitor in the camera that is discharged through the flash unit is recharged by a rectified high frequency ac signal which would actually be pulsed dc.
Capacitors discharge immediately only if they are furnished with a low resistance discharge path such as the flash unit on the camera. Other wise they will hold their charge for at least several minutes in this application.
No they do not put a resistor on the minus terminal of the capacitor because the resister would dissipate too much of the limited amount of energy that is stored in the capacitor`s dielectric and used to activate the flash unit. A resistor would serve no useful purpose anyway. Ideally nothing is in the capacitor`s discharge path but the flash. The button that is pushed to open the lens and take the picture also at the same time completes the circuit from the capacitor to the flash unit and thus activates the flash.
The reason it takes a measurable amount of time to charge the capacitor is because each DC pulse that adds charge to the capacitor contains a very small amount of charge so that it takes many repetitions of the pulse to charge the capacitor enough to successfully activate the flash.
your wording indicates you know little about electricity.
Note that 300 volts will easily kill you (or someone else), and the caps will hold charge for a long time after the power is turned off.
Also note that these home-made "tasers" are very dangerous and are illegal in some areas. If you hurt or kill someone, you could face jail time.
Now to your questions ...
"DC voltages don't work when using transformers to get the electricity up to 300 volts"
You can't use a transformer on any DC voltage.
"Does the camera use a pulsed DC current"? No, it uses a high frequency AC applied to a transformer.
"capacitors discharge immediately" false, capacitors hold their charges for quite a while. They only lose charge through leakage currents.
The rest of your question seems to be predicated on "capacitors discharge immediately" which is totally false.
.