High Altitude Balloons
I got involved in a high altitude balloon interest group, out of the Electrical Engineering department at my Alma-Mater The University of Maine.
When you sit down and think about it, there is much more to high altitude ballooning than filling a balloon with Helium (much safer) or Hydrogen, fastening a radio to it, and letting it go. Issues range from meeting FAA guidelines to how do I retrieve several hundred dollars worth of payload?
What happened to my data?
Where did the balloon go?
How high up did it go?
How do I get it back down... safely?
And... of coarse, the age old: "...why didn't that work like I thought it would...?"
Keeping all this in mind... we can do some "what iffing":
What happens to terrestrial antennas at high altitudes ?
Here's a 70cm Quagi antenna that might be useful for telemetry.