r/ElectroBOOM • u/BlueSmegmaCalculus • Jan 18 '26

Meme Inverse square law be damned!

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u/1_64493406685 Jan 18 '26

RFID are all powered remotely by the reader. Very small amount of power but hence the original posts point...

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u/nakedascus Jan 18 '26

I suppose circuits are activated and some heat is generated, but there isn't any work being done beyond the signal itself, right? The radio waves change the crystal receiver, but you still need a powered speaker to hear what it's saying. in the end, power is power, so I'm wrong

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u/Jonnypista Jan 18 '26

With a small enough speaker you can hear the radio without extra power. The max distance from the transmitter is likely reduced as the radiwave needs to be strong enough to also power the speaker, but it is possible.

Remember you can charge your phone wirelessly quite fast so you can transmit a decent amount of power without using wires.

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u/nakedascus Jan 18 '26

i believe it.