Project help - Induction, sort of

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whatcansixdoforyou
 
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Project help - Induction, sort of

Post by whatcansixdoforyou »

This is a shot of the "root system"
This is a shot of the "root system"
375986_10201087057321863_1561918280_n.jpg (51.96 KiB) Viewed 239 times
I tried looking for the answer but I'm not very knowledgeable and not sure if I am looking for the right thing.

I have a project I started using copper which inadvertently became a giant collector, I understand now what is causing it (mostly) - Here is the link to what I have posted https://hackaday.io/project/4705-a-tree ... n-brooklyn

What I want to do is use whatever is being collected to power some led's, which in theory seems pretty simple...

QUESTION: I'll only be using a handful of led's - Do I need to wire something like this Inductive Charging Set https://www.adafruit.com/product/1459 or Could I just solder a wire from the copper tree to the led and ground the negative to one of the wall studs? or Do I need a capacitor to store the charge til it builds up enough to power the led's? or Am I completely off base?

I apologize if this isn't clear, I'm more of a artist/builder maker than an electronics maker.

Thank you in advance for any consideration and guidance.
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All wiring will be done internally, the led's will be placed so they look like small buds on the branches
All wiring will be done internally, the led's will be placed so they look like small buds on the branches
399935_10201087058561894_1876089871_n.jpg (29.25 KiB) Viewed 239 times

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whatcansixdoforyou
 
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Re: Project help - Induction, sort of

Post by whatcansixdoforyou »

Sorry about the picture location - I can't figure out how to edit

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adafruit_support_mike
 
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Re: Project help - Induction, sort of

Post by adafruit_support_mike »

What you have is basically an antenna.

The large, changing electromagnetic fields produced by nearby trains are pushing the natural, random motion of electrons in the copper around until they form standing electrical waves in the tubing.

In that state, you can't get much work out of the standing waves. What you really want are two antennas pointing in opposite directions that sort of counterbalance each other.. when the external field pushes current up one end it pushes an equal amount of current down the other end. If you put a circuit between those two parts, you get a potential difference that can do something interesting.

That kind of antenna is called a 'dipole'.. two 'poles' pointing in opposite directions.

The neat thing about dipoles is that you can use the whole planet as one pole. The math to prove it gets hairy, but it all works out.

To get power from the antenna, you need to connect a wire to the bottom of the copper assembly, then connect another wire to Earth Ground.. something that has direct electrical contact with the soil, like a water pipe. That should produce an AC voltage/current in the two wires.

The first thing to do once you've made those connections is to hook the wires to a multimeter and get AC voltage and current readings. I'm not sure you'll get enough power to run even a single LED, but thirty seconds of measuring trumps a lifetime of speculation.

If it turns out that you do have enough power, LEDs are exactly the thing you want to use. Current can only flow through them one way, so you get clear "yes, current is flowing" and "no, current isn't flowing" conditions called 'rectification'. Each LED will use half the power available between the wires, so you can put two LEDs in parallel but pointing in opposite directions to use the whole wave.

Start with just the wire connections and meter readings though.. that will give you a better idea of what you're working with.

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whatcansixdoforyou
 
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Re: Project help - Induction, sort of

Post by whatcansixdoforyou »

Thanks Mike :)

I'll be doing a bit of reading and a couple experiments this weekend, did a search for dipole antenna which led me to some really fascinating stuff. Dipole antenna led me to fractal dipoles to energy harvesting to atmospheric electricity to electrostatic motors - Crazy patents going back to the 20's - really neat rabbit hole!

Andy Doro's Table For Electronic Dreams a while ago which is what inspired me to travel this path - Stoked to dig in and play around with this antenna concept now.

Thanks again!

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