Dave, thanks for the reply. I made a solenoid (transmitter), and a spiral (receiver), aiming for around 1 W of power. I was pretty surprised; I was able to light an LED pretty brightly using a diode rectifier. However, measuring the voltage and current across the led, I was reading 2.1 V, and 12 mA, respectively. Unfortunately, this does not equate to a lot of power. Assuming I've done everything correctly (which certainly might not be the case), what do you think the problem might be?

I'm thinking that the solenoid transmitter and spiral receiver combination might not be a good way to transfer energy. I currently have the coils facing each other about 5 mm apart. I'm trying to keep the receiver coil small, thus, I decided on a spiral shape. Is there an 'efficient' coil shape for energy transfer I should be worried about? Your mousepad and cellphone coils seemed to transfer energy no problem.

Maybe the push-pull driver I made from your designs might be inefficient. I haven't tested that portion too much yet.

Another possibility that might be affecting my results is that I am using 26 awg wire to make my coils. Maybe I should try a lower gauge?

What I'm thinking about trying next is a spiral transmitter/receiver combination.

I'd appreciate any input.

Thanks,

Mark