series circuit questions
 

i dont Know how this thing works-
Series circuit - 3 LEDs - YouTube
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Chris Angel Mindfreak

Magic?

Look at the wires between the LEDS. There is no reflection off the wires when the LEDs come on. I expect this is editing.

not a clue

i looked for teltale signs of edits, if there are this guy is good-

not in my bag of tricks, but the distance from the switch to the the light is equal, approximately, for each of the lights. has to do with resistance.

Each LED has a tiny inductor (L) and capacitor (C) across it. Each LC pair is tuned to a different frequency. The LC is a short at DC, but at f1, f2, f3, go high impedance and allow current through the corresponding LED. The switches have a resistor (R) and capacitor (C) in parallel across them. The C large enough to allow f1, f2, f3 through, and 3 different values for R. The battery has 3 oscillators, each of which is enabled depending on the DC current value - set by switches.

that was a quote from the youtube uploader

I'm assuming you know what that means Todd?

I do.

Basically it is a trick. The battery is not putting out DC, but three different frequencies due to the crystal oscillators. The switches each act as a filter to cut off a frequency. The LEDs are tuned to resonate (light up) at a certain frequency, so depending on the switches' positions, different frequencies reach the LEDs and only the LED that is tuned for a certain frequency will light up. Any other frequencies will not cause it to light up, unless the resonant frequency is also coming in (since you can superimpose frequencies).

This is mostly a demonstration of the cool things you can do with resonance.

Well my degree in Electrical Enginnering does sort of help to decipher it.. but thanks for the vote of confidence Sid :D

Resonance isn't limited to electrical circuits. Doesn't take an EE to understand the basic concept. ;)

Well, I didn't get it, I hoped you did.....

You understand resonance, right? That is the heart of the matter.

Think Tesla. :)

He he he. :D

Not quite as far as earthquake machines, though.

One of these cold, rainy days, I'm going to build a small Tesla coil again. :D

I'm a big fan of Tesla and his work.

Yes, your explanation was a wee bit more simple... Todd was just speaking above my head.


I've had a few physics classes, but I didn't listen well...

How about this guess? The battery conceals three oscillators. The switches contain a band reject filter each set to a different frequency i.e. it passes everything that is not in band. The LEDs contain a bandpass set to their respective frequency that goes to the lights.


But I sure don't see all that hardware

Gee, how did you come up with that?

so here is how he did this

Solution - series circuit 3 LEDs - YouTube

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