alt Hacker NewsFANTASTIC!!
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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If you buy three (or more) Phillips Hue bulps you can have them respond to motion detected by things moving around and disturbing the radio waves they use to communicate. So they must have pretty much the kind of map you want, but I dont know how easy it is to export it.
This is sort of that idea with sound:
> and you were able to (somehow?) from the antennas perspective, see the "direction" the frequency was coming from..
You can kind of do that quite easily at low frequencies, by measuring the phase of signals coming in from a pair of aerials. If you put two aerials a quarter of a wavelength apart and switch between them very quickly at audio rate, then you'll get a tone when there's a difference in phase. If there's no tone the two signals are exactly in phase - the two aerials are exactly the same distance from the transmitter.
If you look on some police cars you'll see a group of four aerials about 15cm apart stuck to the roof which used to be used for "Lojack" style trackers.
There are a whole bunch of circuit diagrams floating around for doing this kind of thing, with the simplest being Ye Olde 555 timer and a couple of PIN diodes!
Yes it has been done: https://youtu.be/sXwDrcd1t-E?si=V75bEPMT8qGbo1wG