> Haven't you hear about a story, about 5 years ago, two > Russian scientist kept a cell phone link for half an hour > test and a raw egg near one of the unit is well cooked? > This is not even a 3G device. Such stories need to be examined carefully. A typical cellphone is liable to have about 500 mW input to it's transmitter and most of this would be unlikely to be coupled to a nearby egg. 1 2 3 or 4 G is almost certainly irrelevant. Raw power dissipation is liable to be the main issue here. Dealing only with thermal issues, which is what is suggested here, the egg would need to be raised to say 80C or more. If ambient was 20C then delta T is 60 C so thermal loss from egg would need to be less than 120 C/W. I'm not going to start to try to work out the R value required but I'm certain that a half Watt source in the very centre of an egg would not raise it to anything vaguely approaching 60C above ambient. 10 Watts at the centre would certainly do severe damage to an egg but still not get it anywhere near that rise. Russell -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist