# Wireless power oscillation

I saw a iinstructable on how to build a wiress power coil (http://www.instructables.com/id/Wireless-Power-Transmission-Over-Short-Distances-U/) It calls for a 147.7 kHz square wave.

My question is can I use an arduino to produce a 147.7 khz square wave?

The pwm will easily do these speeds, the instructions call for '147.7 kHz square wave AC' the pwm is DC, a small circuit should fix that.

How do I calibrate it to 147.7 kHz and how do I make it AC?

tone() should do it - http://arduino.cc/en/Reference/Tone

Don't know about the DC to AC conversion though.

Apparently I need to supply the primary coil with AC. Is there any way an arduino can do that, or do I just need to invest in a function generator?

Apparently I need to supply the primary coil with AC. Is there any way an arduino can do that

No. Not unless you connect an AC battery to the Arduino.

There's no way you can do do opposing tones on two pins so that it uses two dc tones to make a single AC tone? That was an idea I had but I have no idea where to start that in a program.

There's no way you can do do opposing tones on two pins so that it uses two dc tones to make a single AC tone?

That is correct. How could two positive voltages produce a negative voltage?

Magic

Magic

This section of the forum does not deal with magic or wishful thinking. Project Guidance is the area for that.

Perhaps you can get an apparent ac, two exact square waves but 180 degrees out of phase then between those pins you will get an apparent ac signal as the positive and negative sides flip flop

That's sort of what I was thinking, but I don't know how do do it or if it would even work.

Basically you can get an h-bridge meant for a dc motor, and wire it to the coil instead, you'll need to check if the h-bridge can be switched that fast

Would the ardumoto shield work?1 http://www.sparkfun.com/products/9815

Wellive gotten the programming part down, now I just need to figure out the actual hardware, which I will do an a different section of the forum.

DC -> AC conversion is done using something called "Inverter". There are ICs that do this job quite easily, and the cost of the IC, apparently increases with the amount of current you want to put out.

http://en.wikipedia.org/wiki/Inverter_%28electrical%29 is an excellent source to get started.

BTW, the answer was "DC to AC circuit" way, on your favourite search engine. :)

True, but a square wave would probably be possible with as cheap as four transistors : )