Has anyone done this before?

OP here, would a suitable alternative just be SDR? With radio can I setup an encrypted chat with just one other person on the same freq and device? would only be good for communication, but not for networking computers together. I've looked into have a solar powered arm boards but are very expensive from where I live.

Not without permission from the FCC. On the bands that are open for public use, such as CB, or HAM ones if you get a license, it's illegal to use encryption. You could still use numerical codes though, like the police do.

What about walkie talkies? Do they follow the same law? Do they have encryption I am from the UK btw.

set up some stupid live stream and mix encrypted data into it steganographically. then nobody would prove that it uses encryption.

Modems over the phone.

Great idea, seriously. That shit worked fine for us in the 90s, and there's probably a decent range of open source software that could make chatting and file transfers much easier than it used to be.

It wouldn't be as bomb-proof as directional antennas, but if the phones are gone electricity is probably gone too.

Still, use the maximum level of encryption possible.

Taken to the logical extreme, you could set up a text to speech program that reads the encrypted message into the radio and the other side then converts it back to text and decrypts it. Encrypting the signal itself is only banned because it's indistinguishable from jamming, but, as you said, transmitting code using human voice is legal.

but is encryption over phone legal?

is powerful transmission of a looped forever Rick Astley song considered jamming?

This is a very good question. I'm interested too.

how much money do you want to spend OP?

You don't even need a powerful transmitter. Just spoof SSID and pretend to be some popular wifi hotspot, devices will automatically connect to you and then you just redirect all traffic to the custom rickroll page. Even 2$ ESP8266 can do that.

I am a student so as little as possible, would that work with the images you've provided?

en.wikipedia.org/wiki/IEEE_802.11s

Nice.

you mean, all non-TLS traffic?

and we were talking about jamming, that is, making other signals physically non receivable

You can always use SSLStrip. Since they are connecting to your network you can do whatever you want with packets comming from their devices including rewriting https requests to http. For only jaming you can just send deauth packets. There is a great tool for that: github.com/DanMcInerney/wifijammer

If they request https, then there's nothing you can do other than first replying with wrong certificate, which will trigger huge warning in all modern browsers.

You're also forgetting websites configured to use HSTS, SSLStrip won't work.

You are right. If they enter https:// before url you can't redirect them, best bet then is to create captive portal page as presented in video and trigger helper that will open "login" page. Since https requests wont point anywhere and will time out, users will suspect that they need to "login" and there you can rickroll them. SSLStrip wouldn't be of any use in the first place for trolling purposes since you wouldn't be doing MITM attack anyways.

Would anyone recommend any arm boards that are really cheap and what solar solution should I use?