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Energy-Harvesting Electronic Holiday Card 2024

keacher.com

1–10 of 26 posts

Re: Energy-Harvesting Electronic Holiday Card 2024

#2
I read the technical description of this and the whole work seems like magic. Antenna design, extremely low-power passive networks, etc. On top of that, it can tap into network signal bursts as a communication medium.

It feels like a project sent from the future.

I've always been curious what energy harvesting systems are capable of.

Also, what is the third type of energy harvesting besides light and 2.4GHz? I couldn't figure out what that might be.

Re: Energy-Harvesting Electronic Holiday Card 2024

#3
post #2

I read the technical description of this and the whole work seems like magic. Antenna design, extremely low-power passive networks, etc. On top of that, it can tap into network signal bursts as a communication medium. It feels like a project sent from the future. I've always been curious what energy harvesting systems are capable of. Also, what is the third type of energy harvesting besides light and 2.4GHz? I couldn…

Heat, voltage drop, and vibration are some other methods.

Re: Energy-Harvesting Electronic Holiday Card 2024

#4
post #3
post #2

I read the technical description of this and the whole work seems like magic. Antenna design, extremely low-power passive networks, etc. On top of that, it can tap into network signal bursts as a communication medium. It feels like a project sent from the future. I've always been curious what energy harvesting systems are capable of. Also, what is the third type of energy harvesting besides light and 2.4GHz? I couldn…

Heat, voltage drop, and vibration are some other methods.

This card apparently has three - but none of those additional ones you listed, unfortunately.

Re: Energy-Harvesting Electronic Holiday Card 2024

#5
Back in the days of 2G the pre-wake-up pulses, aside from causing massive FM/AM interference like demented Morse code, would light up tuned antenna spark gaps on stickers for your Nokia phone. In Japan they sold cute phone tokens which had glowing eyes.

Energy harvesting the same way Theremin did for his passive wall bug.

Re: Energy-Harvesting Electronic Holiday Card 2024

#6
post #2

I read the technical description of this and the whole work seems like magic. Antenna design, extremely low-power passive networks, etc. On top of that, it can tap into network signal bursts as a communication medium. It feels like a project sent from the future. I've always been curious what energy harvesting systems are capable of. Also, what is the third type of energy harvesting besides light and 2.4GHz? I couldn…

“At its core, the card harvests energy from light, radio, and/or a USB connection to enable the blinking of LEDs.”[0]

So the last is USB, the sneakily obvious one.

0: https://www.keacher.com/xmas24/tech_info.htm

Re: Energy-Harvesting Electronic Holiday Card 2024

#7
For a while I had a very overpriced phone case from moeco that lit up when cell service was being used - https://www.moeco.jp.net/ - it came with a big warning not to use wireless charging with it (due to instead heating the case). Sadly, I wouldn't get one nowadays, I love wireless charging too much.

Re: Energy-Harvesting Electronic Holiday Card 2024

#9
Interesting, thanks for sharing.

One question: what load is the matching network designed for? Did the designer find the equivalent small signal impedance of the diode network via simulation? Is the SPICE model even valid at 2.4 GHz? Is small signal even applicable?

Re: Energy-Harvesting Electronic Holiday Card 2024

#10
post #5

Back in the days of 2G the pre-wake-up pulses, aside from causing massive FM/AM interference like demented Morse code, would light up tuned antenna spark gaps on stickers for your Nokia phone. In Japan they sold cute phone tokens which had glowing eyes. Energy harvesting the same way Theremin did for his passive wall bug.

Tuned spark gaps? Or just an antenna hooked up to a pair of back to back LEDs? Just recently I saw something about light-up fake fingernails that would blink when you got a 2G phone call.
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