I want to build a mobile phone jammer
- short range (not more than 5 yds)
- handheld, small
- battery powered
so that when I'm on the bus/train and some idiot start loudly talking about his business, I can press a button and cause just enough interference to disconnect him mysteriously.
It would be better if it had some directionality but not too much. I don't want to aim it at someone but it would be nice to be able to disconnect the loud phone user in front of me without affecting the text messager behind me.
Can anyone point me in the right direction for designing this?