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by TheOtherHobbes 1865 days ago
1. No, because the power has already been transmitted. There would be problems if there were billions of these devices around a transmitter, because that would affect the loading. But one isn't going to make a difference.

2. Potentially yes, but the actual shadow is tiny. And transmitter powers are fixed and limited anyway.

3. Yes, of course. So is any form of undirected radio transmission.

4. This actually works. Kind of. You need to run the line parallel or build a resonant mix of L and C at 60Hz (or 50Hz.) You can also do things like power fluorescent tubes by induction.

https://www.trendhunter.com/trends/magnetic-field-fluorescen...

The problem is the voltage/current is very hard to control, and the whole point of electric fences is that they're not lethal. You'll get something out of a resonant circuit, but if you're not a qualified electrical engineer it won't be the clean 110/60 or 220/50 needed for an electric fence.

2 comments

It only works because the LC circuit has a high "Q" and it peaks up at resonant frequency, at the expense of current. It is sort of like a torque convertor for electricity.

Now in most applications a minimum voltage is required and you will counter the small current by using a capacitor to accumulate power, at a usable voltage, until you have enough to briefly do something.

I would make a YouTube video if I could be arsed, but way to busy right now.

Points 2 and 3 seem like they could contradict each other. Wouldn't a tiny amount of power for you equate to a much larger amount of power at the radiation's source?
No. The transfer is inefficient because the vast majority of the transmitted power is dissipated in the environment as heat.

The transmitter cannot tell if switch the receiver on and off.