Why not change the batteries to Lithium (they weigh less) and put out a lot
of power for a long time. Go into the radio and set the power output on
"high" to 2 watts, which is a big improvement from 1/2 watt and not as
demanding as 5.5 watts output.You might be able to wire the batteries for
more amphour rating and a lower voltage due to the need for 2 watts, further
extending it's ability to transmit for a longer time. Since the GPS data is
streaming, you could even set the transmitter to "burst" or send it's data
in 10-15 second bursts every few minutes, extending the batteries even
further. Hope this helps....Eddie

"David Harper" wrote in message
om...
I'm sending a IC-V8 (2m) up on a high altitude balloon, and was
debating on what power setting to use. Ideally, I'd go with the
higher power setting (5.5W), but due to the cold temperatures that are
encountered (even with insulation) and limited battery life (even with
a higher capacity battery), going with .5W is more reliable from a
battery life standpoint. Also, I'm using an audio sound module (not
packet radio) to relay GPS information back.

My question is: can I get clear reception using the .5W power setting,
even when the balloon is, say, 75 miles away at an altitude of 20
miles?

Thanks in advance!
Dave