Instructables

How to pulse dc current?

Hi! I was just wondering if people could give me some different ways to pulse dc current. I am trying to power a transformer with dc. Thank you in advanced.

Re-design2 years ago
Wire the relay so that it's own power goes thru on set of terminals that are normally closed. That way when the relay gets power it will pull in and break it's own circuit. Then it will open again and complete the circuit. It won't be very fast though. Maybe only 4-10cycles per second. You control the other devise by using one of the other terminals that are normally open. It will then be pulsed as the relay pulls in and off when the relay releases. So you need a relay with one set of terminals that are normally open and another set that are normally closed. They also have to be heavy enough to carry the load for the transformer.
tesla man (author)  Re-design2 years ago
Ok, and how does the transistor coil work?
what voltage are you trying to switch?

It would be something like this.
iceng2 years ago
A 556 is a dual 555 in one package :-)

A
12V- complimentry556AC.png
sk8aseth2 years ago
A simple solution would be to use a 555 timer, but it depends on the frequency you need for you transformer. A 555 can go up to about 50khz before getting seriously distorted. Here is an example where one is used to drive a flyback: http://jnaudin.free.fr/html/lwhvps.htm
tesla man (author)  sk8aseth2 years ago
I guess i could., but before i pick what to use, i am just having people come up with idea
Re-design2 years ago
you could set up a relay so it would work as a vibrator that would chop up the power.

You could make an oscillator out of a transistor, coil and capacitor that would chop up the power.

You could make a multi-pole rotary switch connected to a motor that would chop up the power. You could buy a old but working vibrator that used to be used in 40's car radios that used tubes.

You can still find them on ebay and I even have one im my collection of old stuff. You could hire somene to flick a switch off and on real fast. I would work better if you used a dpdt switch so you could wire it to reverse the current.

You could use a 555 timer wired as an astable multivibrator to chop the power.
1st; this is a great list of alternatives, best answer (then again, you have no competition at this time)

2nd; looks like you are offering yourself... (or is that "I" a typo :-):

"You could hire somene to flick a switch off and on real fast. I would work better if you used a dpdt switch so you could wire it to reverse the current."
That should have been "it would work better".
tesla man (author)  Re-design2 years ago
Yes, i heard about the vibrating relay, but how would you make it?