I believe the unliciensed 900MHz band is restricted to 30mW xmitter output
in the USA.  The actual frequency is also important, i.e. 915MHz.  With a
3db antenna and line-of-sight you should be good for 1 mile.  Remember
antenna placement, to escape ground effects it needs to be about 35 feet up.
Each country has differing requirements.  The 2.4GHz band seems to be the
most liberial worldwide.  Search for "FCC" and I'm sure you will find more
than you really wanted to know.

Have a nice day! :)
Ryan

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I do not feel obliged to believe that the same God who has endowed us with
sense, reason, and intellect has intended us to forgo their use. - Galileo
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