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I built a light that reacts to radio waves [video]

244 pointsby codethewebtoday at 5:34 AM55 commentsview on HN

https://rootkid.me/works/spectrum-slit


Comments

tzvctoday at 10:49 AM

Creator here, thanks for posting. And feel free to ask me anything!

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TrackerFFtoday at 9:50 AM

Cool project. I was going to say, the end resulting light should be a pretty saturated spectrum, given that many RF sources just keep pumping out waves, and the those waves propagating and bouncing around.

I think one fun application would be a light which represents your wi-fi strength around the house. Obviously in a smaller apartment that's really not a problem, but in larger houses it would be fun to see.

Another application would be to find hidden RF sources / leaks. I have a home recording studio, and for the life I could not find some RF source that kept adding noise / interference. I could roughly detect the frequency of the noise, but not its origin. I guess if I had a couple of RF sensors I could try to triangulate my way to it.

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kh_hktoday at 12:24 PM

Cool project. Here's some OT: where do people learn to make these videos? Fast paced but calm narration with chill music and sped up action mixed with regular speed. It's a matter of consuming a lot of this content until the form clicks, or you need to go to influ-school?

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mrtksntoday at 7:02 AM

It’s beautiful. I think I’ve seen something similar in a Ukraine war video where they use a device that lights up on specific frequencies that drones use.

lucid-devtoday at 7:03 AM

FANTASTIC!!

I was just thinking about this the other day, and wondering about directionality...

For example, if you had a camera facing a space, and the receiving antenna was within that space... and you were able to (somehow?) from the antennas perspective, see the "direction" the frequency was coming from..

And then map the different specific frequencies within the desired bandwidth to colors... and of course intensity map like you have in the slit device..

And then "look through the camera"... you would see a live three dimensional overlay of all signals within range (colored!) "interacting" with the antenna... but kind of more the "looking through the camera" sort of view, like you could "see" how those waves were interacting..

And then wouldn't it be interesting to put a tin-foil hat to one side of the attennas.. and see how the waves change in real time... etc.!!!

(I guess it takes three antennas, to triangulate the field? Maybe all three can still be mounted on a single device in close proximity?)

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cushtoday at 7:10 AM

His other projects are so interesting. I love this one

https://rootkid.me/works/exhibit-a

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asgerhbtoday at 11:30 AM

Sawing the first shot, I thought the LED candle on the coffee table was the device. That would have also been cool, having flickering affected not by wind, as with real candles, but by radio waves.

01100011today at 8:54 AM

A much simpler and less cool project would be to convert a slice of the RF spectrum into an RGB value with lowest frequencies mapped to red, highest to blue, and the resulting color being how we would perceive the mix.

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fnandstoday at 10:11 AM

Very cool! I was having a conversation with my colleagues yesterday about building something to detect when you get scanned by a SAR (synthetic aperture radar) satellite (we're in earth observation), but you'd have to get a directional antenna to not be drowned out by terrestrial radio signals.

sergioisidorotoday at 11:01 AM

I just watched all the other videos of their pieces, and all of them are absolutely amazing conceptual explorations of our relationship with technology. Really amazing stuff

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milleramptoday at 6:39 AM

Very cool, was there a conversion or look up table to convert db to gamma for more accurate human visualization?

alansabertoday at 10:42 AM

I'm glad we can all agree this is really cool

ameliustoday at 8:51 AM

All those inductors... Isn't there a cheaper way to drive those lights, e.g. using DC voltage+pwm?

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sush1612today at 11:11 AM

you have everything right in front of your eyes, next if you add a transformer which convers these light signals into what they actually are then Voilà, you can see what's travelling in the air (Photos, conversations, music)

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ggmtoday at 7:06 AM

I cannot find the YT video but an artist in residence did a short film with scratch-over of footage in an RF lab which tries to give a visual impression of the waves emitted by things present.

We're bathed in EMF. It's what light is, but aside from that we use electricity so much now, we're in a sea of radiation in other frequencies too.

Suractoday at 9:01 AM

I once had a antenna with a lamp on it. It was used to detect best place for the radio. It just rectified the energy it received and used a very tiny light bulb

shawn10067today at 7:01 AM

This is such a neat project. The idea of translating invisible radio waves into visible light is mesmerizing — it feels like giving your surroundings a new sensory dimension.

smellingtontoday at 9:08 AM

Very appropriate soundtrack too:

https://youtu.be/B_gLxVZuk60

Uranium by Radioactiveman

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dyauspitrtoday at 6:54 AM

This is fantastic. But the idea where you use a camera that can only see the wifi signals in the room like visible light is even more stunning. It would be even better if you could block out all light from the visible spectrum and only see the GHz band.

mock-possumtoday at 6:42 AM

Incredibly cool. I was really hoping to see the more ‘edge’ cases - take the light out to the middle of nowhere, walk towards it and away from it with just your phone or a Bluetooth speaker, see it react to your approach. The bit at the end about it shifting over the course of the day is cool, but I wish the effect was more visually apparent - it mostly just looked like random noise the whole time to me.

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cushtoday at 7:08 AM

The sounds were so cool -straight out of sci-fi movie.

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mw67today at 7:04 AM

Someone makes a kickstarter out of it please

steevetoday at 10:54 AM

very very cool !

louwrentiustoday at 8:04 AM

Let's call this what it really is: it's an art project. It's not 'just' a cool technical work.

[0]: https://news.ycombinator.com/item?id=46729428

segalordtoday at 6:36 AM

I love your poetry on a phone project so muchhhh

ebhntoday at 6:36 AM

Very cool!

pKropotkintoday at 10:42 AM

Why do you need another source of irritation in your room?

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