i remember seeing a while ago a device (possibly in a pen) which flashed when a mobile phone went off close to it. anyone know if these have a proper name and if you can buy them in any particular shops (not online)?
if anyone's interested it's gonna be for a jokey xmas present, my sister never replies to txts so i'm gonna try and cannibalise it and wire it up to the loudest buzzer i can find. and yes i know i've left it very late, i'm a procrastinator.
if anyone's interested it's gonna be for a jokey xmas present, my sister never replies to txts so i'm gonna try and cannibalise it and wire it up to the loudest buzzer i can find. and yes i know i've left it very late, i'm a procrastinator.