This past Thursday afternoon I received my new Arrow Antenna. It's a dual-band (2m/70cm) handheld yagi antenna made from aluminum arrow shafts for making contacts with amateur radio satellites. What? You didn't know there were ham radio satellites? Yep, and there's more than one.
Using Heavens-Above, I can find when each satellite will be making a pass over my location as well as the angle and direction of the approach and apex. About an hour after I got the antenna, AO-27 was making one of its daily passes over me. I made sure everything was in order, set my radio to the right frequencies and walked to the field across from my house. Right off the bat I heard guys in New England talking with guys in Florida. Most everyone on the air was using a handheld with relatively low power (under 5W, which normally isn't enough to even get you across town). After just a few minutes I heard my chance to throw out my call. Right away I had two stations come back to me. First time to ever hear the satellite and I was making a contact on one. Unfortunately I didn't have a free hand to write down his callsign and I forgot it! Oops!
How does it work? Essentially the little satellite takes my signal and rebroadcasts it like a ground-based repeater does, only it's up - way up. Because it's up so high, it can rebroadcast my signal to most of North America. To hear me all the other station has to do is listen on the "downlink" frequency.
Really it doesn't take any special antenna to allow this, it's just this antenna is very efficient and easy to aim at just the right spot. Sometime in the future I'd like to try to make an altazimuth mount to automatically steer the antenna for me, but that's way down the road. For now I'm just looking forward to the next satellite pass!