I've been toying with the idea of transmitting data at a low bandwidth using soundcards and walkie-talkies, but the range of a cheap walkie-talkie is very low, a fraction of a nautical mile in fact. This could presumably be improved by some kind of dish which focuses the signal onto a particular point, possibly several minutes of latitude away, but this would have to be precisely aimed, the focal point would be hard to locate and jogging it slightly would shift it to the houseboat next door or something, plus all the bobbing up and down would make it difficult. So, what if instead of having a dish something like a metal tube or pipe were used between two walkie-talkies? Would this not increase the range of the signal? Obviously i'm talking about on land, not in the water.

Also, if you had two mobiles/cellphones using Bluetooth, could you not then communicate using such a tube over a greater distance, if you only ever texted (et caetera) one person?
-- nineteenthly, Apr 30 2010

Cantenna http://www.turnpoin.../cantennahowto.html
Typical homebrew antenna for the 2.4GHz range (WiFi & Bluetooth) [Jinbish, Apr 30 2010]

Bluetooth private chat network Bluetooth_20private_20chat_20network
Similar [8th of 7, May 21 2010]

Or two short, closed-at-one-end tubes, connected by a length of string.
-- coprocephalous, Apr 30 2010


Or better, coaxial cable ...
-- 8th of 7, Apr 30 2010


You two are a Twisted pair...
-- Jinbish, Apr 30 2010


Yes, i was thinking of coaxial cable as well. Would it also mean the signal would be less detectable from elsewhere?
-- nineteenthly, Apr 30 2010


yes. a good coax cable has almost no leakage.
-- batou, May 07 2010


Coaxial cable connecting two appropriate antennae should work fine for walkie-talkies, but cell phones would need to connect via a local tower...
-- csea, May 07 2010


Once the tube was in place, you could dispense with the electronica and use the tube for communication. You might want to make the tube flexible.
-- bungston, May 07 2010


[Csea], not so - Bluetooth.
-- nineteenthly, May 07 2010


//not so - Bluetooth//

OK, please elucidate... Do you mean that two Bluetooth microphone/earbud devices would connect to each other? I don't see how this could work.
-- csea, May 21 2010


They'd need to bond with a local server that could sustain a PAN.

<link>
-- 8th of 7, May 21 2010



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