Instructables

how do i make an ac current with a battery?

hi,
i have searched over the internet many a time, looking for how to make pulsating dc or an ac current, however all my results end up with devices which use ac or pulsating dc, which is comming from some homemade ac-dc converter running of mains.
now, i am trying to find out how i can use a aa battery to aquire an ac current, or pulsating dc current,
preferebly using parts aquirable from a disposale camera.

the reason i need ac or pulsating dc is so that i can build a voltage multiplier, and also a tazer.
i have tried plasmanas instructable on making a worlds smallest shocker, but it just doesnt work, if you cant get the specific transistors and transformers only aquirable from polaroid brand disposable cameras. plus there are no details on where to buy the parts, or even their details, beyond resistance and capacitance values.

the main thing though is that i need to make the pulsating dc or ac from a portable power supply, aka a battery, as i also wish to make a dc-dc boost converter to use on different components within my rc tank.
please help, whoever can answer my question best will receive a " best answer"

raja262 years ago
Try the joule thief setup, it is very simple.. The input part has a transistor which creates pulsated DC from battery.. Search "Joule Thief" in instructables and try any circuit.. The toroid works like a transformer (increases the voltage).. So it might help your need.. Try high voltage Joule thief for high voltage applications..
thank you.
orksecurity3 years ago
The difference between AC and pulsating DC is the waveform and what voltage you arbitrarily call zero. A DC to DC converter is simply an oscillator to convert DC to a pulsating or sinusoidal waveform, put through a transformer to get higher voltage (and lower amperage), rectified to re-establish the zero-volt line so it can be treated as pulsating DC, and then filtered appropriately to smooth out the pulsation so you get continuous AC.

There are lots of DC-to-DC converter circuits on the web, including a fair number right here on Instructables.
jpoopdog (author)  orksecurity3 years ago
however almost all if not all require you to already have pulsating dc, or some expensive device which has been improvissed to do so
Hm? I think that's demonstrably untrue. See the Voltoids project, as one of many examples of stepping up a battery's voltage.

Of course that's starting with a small battery which can't supply many amps, and isn't designed to handle many amps of load. But as I said, the more you increase the voltage the fewer amps you're able to draw; if you want a substantial amount of power out of the converter, you'll have to use it to slowly charge up a capacitor or something else that can rapidly deliver its accumulated power.

Which is exactly what that flash circuit does. It charges the capacitor to a few hundred volts over the course of a minute or so, then releases that energy in a tiny fraction of a second to fire the xenon flash tube.
Re-design3 years ago
Take the disposable camera and take out the capacitor and the step up transformer.

At the connection that fed the step up trans. you will get either some oscillation voltage or intermittent dc.

Now use that for your purposes.
jpoopdog (author)  Re-design3 years ago
i shall try this, i pray it works
Now that I've had time to think, the charging circuit "may" use the primary of the transformer as part of the oscillator circuit.
rickharris3 years ago
This is more than likely a non starter for you unless you can get a suitable inverter to change the DC to AC.

There are several electronic ways to go and even mechanical ways - do a search for inverter circuits and interrupters (the mechanical version)