Comment Re:Already have one (Score 1) 296
Real phones also pick up that kind of interference - you can hear the mobile of the person on the other end of a phone line (perhaps in a different country) before it rings. Spooky for the other person if they don't realise what the diddly-dit-dit-dit noise is and you tell them their mobile is about to ring :)
Over Christmas a friend gave me a cheap tacky little reindeer hat thingy that you stick on top of anything nearby. The reindeer nose (led) lights red whenever there's significant radio activity from nearby mobiles. Sold as a cheap piece of Christmas fun that light up when _your_ mobile phone rings, of course it actually lights when any nearby phone rings, sends or receives an sms, etc.
Another friend has a similar circuit built into his car air freshener, which similarly flashes whenever there's mobile phone activity nearby.
Incidentally, I'm not sure measuring distance would be all that accurate, just based on signal strength. The latter depends on the power of the mobile phone's transmissions, which depend on how good a signal the phone gets from the base station...
Over Christmas a friend gave me a cheap tacky little reindeer hat thingy that you stick on top of anything nearby. The reindeer nose (led) lights red whenever there's significant radio activity from nearby mobiles. Sold as a cheap piece of Christmas fun that light up when _your_ mobile phone rings, of course it actually lights when any nearby phone rings, sends or receives an sms, etc.
Another friend has a similar circuit built into his car air freshener, which similarly flashes whenever there's mobile phone activity nearby.
Incidentally, I'm not sure measuring distance would be all that accurate, just based on signal strength. The latter depends on the power of the mobile phone's transmissions, which depend on how good a signal the phone gets from the base station...
