Tell us about yourself!
Hello there! The coupling coeficient k doesn't effect the value of the inductor & capacitor (at least to first order). The value "k" gets smaller as the coils get farther apart. If you want to know the equation for the inductor and capacitor, you can read about it on this website:https://www.allaboutcircuits.com/textbook/alternat...You can always tune the values for different resonant frequencies.
Don't worry, we've already started a Makerspace! :)
It's a pretty cool church! Check it out http://www.the-river.org
Sure, that would work! You could also use an LM555 oscillator. But it would need to be adjustable since you need to tune it to find the ideal frequency.
We picked 8kHz for two reasons. First to be high enough in frequency to allow for a relatively small capacitor (which is important at 500V since anything larger than 1uF is hard to get and is huge). Second to be low enough in frequency to be compatible with cheap audio amplifiers (like PC speakers). It's not noisy. You can hear a little 8kHz buzz, but it's not bad at all -- you can only hear it in a quiet room. When we do presentations, sometimes I hook up a little speaker in parallel just so people can hear it.
So true! In fact, this is a straightforward application of faraday's law, which was discovered in the 1830's. So this is 150+ year old technology! But that's the case for almost all of our technology (Maxwell's equations are now more than 150 years old too). What's different now is that you can easily purchase all of these parts and actually build it yourself -- thanks to Amazon & Digi-Key. We're also lucky to have access to simulators which can numerically solve Faraday's equations. That's why we're lucky to be around now!
Good point, we fixed that, should have been cm, not mm!!
High-Range Wireless Power View Instructable »