"Greg Copeland" wrote in message
news
[...] I'm not sure how far you could even transmit on 0.6 of watt.

FRS (the 90's answer to walkie-talkies) is limited to 0.5 watts and is
considered usable up to about 2 miles (not counting obstructions). Range is
dependent not just on the transmitted power, but also how sensitive the
receiver is. Pitifully weak signals are received over distances of hundreds
of millions of miles on a regular basis (just ask NASA).

Pete