By Stan Horzepa, WA1LOU
Contributing Editor
June 15, 2002
Can't afford a ride on the space shuttle? Try the next best thing: Have an outer space QSO. And here is a Web site that will tell you how to do it.
The Web site of the Radio Amateur Satellite Corporation of North America--better known as AMSAT-NA-- is a comprehensive source of information for anyone interested in exploring ham radio communications in outer space and near space. There you can find information concerning Amateur Radio operations on-board satellites, space stations and high altitude balloons.
One of the essential to achieve communications with orbiting objects is the ability to know when the objects are in operating range. "Line of sight" is the name of the game in this mode; so you must know when the portion of the Earth's surface that is in the line of sight of the orbiting object--that is, the "footprint" of the object, encompasses your station, otherwise, forget about it.
![]() AMSAT-NA (The Radio Amateur Satellite Corporation -- North America) Web site is the place to go to work what is out there in the outer ether. |
Software that tracks the position of orbiting objects is the tool you need to determine the footprint and the AMSAT-NA Web site has a variety of tracking software for a an assortment of computer platforms. The tracking software is useless, however, without the current data regarding the orbits of the space objects. Most tracking applications use "Keplerian elements" (or "Keps," for short, named for the German mathematician and astronomer Johannes Kepler, whose life straddled the late 16th and early 17th centuries) to perform their calculations and, you guessed it, the AMSAT-NA Web site has the current Keplerian data at all times.
Even with the Keps and tracking software in hand, you also need the proper antennas to work orbiting objects. The Web site provides an array of useful information regarding what kind of skyhook to use to work outer space, as well as, how to put that aluminum up there and how to turn it in order to track the orbiting object you are chasing.
Not all orbiting objects are the same. The modus operandi of an object is more likely unique than not and requires special operating procedures for communications. For example, the object's transmit frequency is often on a different band than its receive frequency and the object may use different modes (voice, packet, etc.) on different bands (2 meters, 70 cm, etc.), too. All these variables may be a little daunting to the newcomer, but the AMSAT-NA Web site provides plenty of operating tips to get you over the bumps in your trek to achieving success in the Amateur Radio space modes.
Paul Williamson, KB5MU, maintains the AMSAT-NA Web site and welcomes everyone to try the site.
Until next time, keep on surfin'
Editor's note:
Stan Horzepa, WA1LOU, resides in downtown Wolcott, Connecticut, and is a member
of the QQCC (QST quarter century club), i.e., he has been a QST writer for 25
years. Since getting his ticket in 1969, Stan has sampled nearly every entrée
in the Amateur Radio menu (including a stint as Connecticut Section Manager),
but he keeps coming back to his favorite preoccupations: VHF and packet radio.
As a result, he runs a 2-meter APRS digipeater from his mountaintop location in
central Connecticut. Stan has been a long time advocate of using computers with
Amateur Radio and wrote programs to dupe contests and calculate antenna
bearings way back in 1978. Today, he uses his Mac to surf the Internet
searching for that perfect ham radio Web page. To contact Stan, send e-mail to wa1lou@arrl.net.