Sensing radio frequencies?

So I've been playing with radio equipment recently and found some interesting properties that could potentially apply to biohacking.

I've been driving with a simple citizen band radio setup, a portable battery operated radio with a cheap whip style antenna attached magnetically to the roof of my car. It's been fun hearing all the weird chatter between truckers and other folks, what's really been peeking my interest is the kind of interference you can pick up.

Here's some examples I've noticed so far:

* The ambient radio noise level is greater in my (smallish) city than on open highway
* Power lines nearby will create noise
* Big trucks and some cars passing will have a distinct noise to them, sometimes my car as well
* I can hear lightning strikes from storms both near by and our of visual range. Driving away from the storms I'll hear the strikes fade over time.
* Driving by some bridge construction on a highway, I could hear some kind of welding tool a worker was using from a good 200 feet away.

Now driving around listening to pure radio static for more than 20 minutes personally gives me a headache, but has anyone thought of ways to translate radio waves into a more natural, ambient sense?

Some (disorganized) thoughts:

* Different frequencies may let you hear different things. Obviously you don't have to stick to CB bands.
* How large of an antenna do you need to pick up useful signals? Could you sew something light into a jacket? Could you have a bracelet or a lined glove to listen to feel nearby objects? (fyi I know literally nothing about antennas!)
* A backpack lined with antenna wire + a portable transmitter might not be the most comfortable but might be a simple starting point
* Small battery powered CB radios exist, and I'm sure you could make something smaller that can only receive.
* It might help to run the signal through some kind of mathematical function to boost useful parts, like scaling it logarithmically to better hear changes of ambient noise
* Piping the signal as audio to an ear piece works but there's no way a normal person could listen to radio static all day. Maybe some kind of filter could help to cope with that?
* Have some algorithmic assistance pick out specific interesting patterns and signal it to you instead of the raw signal (although you might miss out on interesting things!)
* Ideally you would want to avoid needing to adjust anything to use it, you don't need to turn any knobs to get your ears to hear different frequencies.
* Pipe the signal to a coil for a magnet implant but, speaking as someone who has had one for a year, I find weak fields fairly difficult to feel so I don't know if that would work well (maybe I just need to train better?)

I'm sure sensing radio frequencies has been talked about before here, but has there been any significant investigation into it? Anyone else have thoughts on this?



  • I think this would be really cool especially as you describe that some things have certain tunes to them, the best place to start for a algorithim would be to reccord a large ammount of static and then sections of say welders and lighting strikes and then write something to check whn it peaks from the normal into one of those maybe then alerting you mayberby a buzz somwhere i don't know.
  • Usually you'd want at least a quarter wavelength (preferably with ground plane) sized antenna to get a good signal. Which is about 3 meters for CB if I'm not horribly off.
    You can pick up signals with smaller antenna but they will suffer from reduced sensitivity. This may not be too bad if you'r interested in local signals only.
    So you may want to look at rubber ducky antenna. They are cheap, with less gain than the big ones, but they are compact. Loop antenna might be interesting too (maybe even with ferrite core). You can get a bit of directional sensing out of it too. 
  • If the only thing you want to do with it is detect, you don't need a power supply at all. Crystal receivers are extremely simple, though you might want a powered amplifying circuit for more distant sources. Of course, you could always try to find one of those old headphone am/fm radios and just modify the tuning coil, too.
  • I was thinking of crystal radios too, but I've never heard of one operating in HF range, so I just assumed it wouldn't work. But if you don't care about actual radio station transmissions it might be a good start.
  • Using a software-defined radio with a cheap computer could allow you to use something like TensorFlow to utilize machine learning to analyze the audio to tune out meaningless static.

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