HAM Radio 101

A Very Abbreviated History of Ham Radio Satellites

Satellites have helped us achieve incredible advances in science, military, and telecommunications fields. They’ve also provided hams incredible opportunities for radio enjoyment. Since the Russians successfully launched Sputnik on October, 4, 1957, and the U.S. response, Explorer 1, in early 1958, there have been a slew of satellites put in orbit. Amateur Radio was not far behind, and today there are over twenty ham radio satellites in orbit, with many predecessors.

How did ham radio satellites come to be? In this article, I’ll give you a brief overview of ham radio satellites (not a comprehensive history), touching on the major developments in the evolution of satellites for amateur radio use. I’ve provided several links at the end of this article for those who wish to read about the history of ham radio satellites in greater detail.

The 1960s: Birth of an Industry
Shortly after the launch of Sputnik, U.S. hams in California began to dream of putting an amateur radio satellite in orbit. After reaching out to the ARRL and the U.S. Air Force, Project Oscar got underway. Like many tech startups of our time, initial work was done in the garages and basements of the Project Oscar team members. After nearly four years of work, the result of their efforts, OSCAR 1, was launched from Vandenberg Air Force Base on December 12, 1961. Weighing around ten pounds, OSCAR 1 sent a simple beacon in CW. It remained in low-Earth orbit for 22 days, and nearly 600 amateurs in 28 countries heard the 2-meter beacon. While the first launch was short-lived, it opened the door for greater experimentation. Several other OSCARs were launched throughout the 1960s, including OSCAR 3, the first satellite with a transponder, allowing hams to communicate through it. Being able to communicate great distances over 2 meters through an orbiting satellite had a dramatic effect on the ham radio community.

In the late 1960s, students at the University of Melbourne completed work on a satellite that would use the 10-meter band to evaluate propagation. It also had a system that would allow the satellite to be controlled by commands uplinked from a station on the ground, via RF. However, they couldn’t get it launched and it sat on the ground for months. Around that same time, several hams met in Washington, D.C. and formed AMSAT, the Radio Amateur Satellite Corporation of America, officially created as a nonprofit in March 1969. Their first project was to help get the Australian satellite launched. Renamed Australis-OSCAR 5, it was put into orbit via NASA on January 23, 1970.

The 1970s: Phases and Evolution
Other nations got involved with ham radio satellite development and engineering. In 1972, Phase 2 of satellite progress began as hams in the U.S., Australia, and Germany contributed to OSCAR 6, which had a 2-meter uplink and a 10-meter downlink. OSCAR 7 was launched in late 1974, and despite being quite fragile and off the air for nearly two decades, it came back to life and remains active to this day. It is one of the oldest satellites still in orbit and still provides a lot of enjoyment for the satellite community. Canadians and West Germans contributed to OSCAR 7.

This international cooperation continued to blossom when OSCAR 8 was launched in 1978, with two transponders on board, one of which was designed by Japanese hams. It provided great service to the international community until 1983.

In the mid-1970s, rumors of the Russians launching their own satellite made it to the West. These rumors ultimately proved true, and the first-known Russian ham radio satellites, RS-1 and RS-2, were launched in October 1978. These satellites had a 2-meter uplink and 10-meter downlink. RS-2 remained active until 1981.

The 1980s: Critical Mass
Before the 1980s, satellite activity was limited to a fairly small group of amateurs willing to experiment. That changed in the 1980s when more launches led to increased activity around the world. It also saw the beginnings of Phase 3. Streamlining their process of providing low-cost, high-quality operations and forging excellent working partnerships with launch providers, AMSAT paved the way for a series of successes in the coming years. Several other countries got involved in satellite launches as well.

The 1980s did not start auspiciously. The first Phase 3 satellite, built by hams from the U.S., Canada, Hungary, Japan, and West Germany, launched from French Guyana on May 23, 1980. Unfortunately, the Arianne rocket failed a few minutes into launch, and the new satellite ended up at the bottom of the Atlantic Ocean. Work began on the next Phase 3 satellite almost immediately.

The Russians were busy in the 1980s as well. Iskra 1 was launched in 1981, and six new Radiosputniks were launched simultaneously in December 1981. RS-3 through RS-8 had 2-meter uplinks and 10-meter downlinks and were quite loud. A few of them had a robot on board so a ham could have a CW “QSO” with the satellite itself. RS-5 and RS-7 were active until 1988.

Meanwhile, AMSAT’s Phase 3B satellite OSCAR 10 was successfully launched in June 1983. However, a series of errors during deployment left the satellite with a damaged antenna and a very erratic orbit. It performed admirably for several years under those conditions, with many successful contacts made.

Students at the University of Surrey built two satellites in the early 1980s. The first, UoSAT 9 or UO-9, carried telemetry beacons and a camera which transmitted images back to Earth. It also carried a voice synthesizer that reported status updates. Even though it didn’t carry a transponder, it was a big technological leap at the time. UO-11 followed in 1984, with beacons and a camera like its predecessor.

In 1986, Japan launched its first satellite, Fuji-Oscar 12 or FO-12. This satellite featured a digital message service with a 2-meter uplink and a 70-centimeter downlink, as well as supporting voice communications. It was incredibly popular. The same year, the Challenger explosion put a halt to some space activities. This would ultimately drive the cost of launches up exponentially, forcing designers to get even more creative about how to launch their inventions.

In 1988, AMSAT launched AO-13, which was the most advanced satellite up to that time. It offered amazing coverage thanks to an orbit that sometimes put it over 20,000 miles from Earth, making it accessible for hours at a time. Real DX opportunities were possible with AO-13, and countless hams took advantage of this bird while it existed.

The 1990s: The Era of MicroSats
Big satellites fell out of favor thanks to rising costs and limited launch opportunities. Despite this, several other countries made it to orbit with their own satellites, including Pakistan, France, Portugal, and Korea.

AMSAT streamlined its approach to satellite building by developing the MicroSat. This allowed several satellites to be worked on simultaneously, reducing costs considerably.

Two major satellite launches of the 1990s were Japan’s ­FO-29 and AMRAD’s AO-27. Launched in 1993, AO-27’s loud FM transponder made it easy for new satellite operators to work other stations. After several years of service, the satellite stopped functioning in late 2012 and went silent. In 2020, recovery efforts proved successful, and the satellite was restored to limited use. It is currently active for four minutes per pass.

Launched in 1996, FO-29 had an SSB/CW transponder with a 2-meter uplink and a 70-centimeter downlink. For over two decades it was loud, reliable, and easy to work. While it was considered a low-Earth-orbit satellite, DX opportunities were possible on a regular basis thanks to a good footprint. While still in orbit, FO-29 is now accessible only by schedule.

The 21st Century: Cubesats, Collaboration, and an Eye Toward the Sky
Smaller satellites and partnerships with universities have led to an explosion of ham radio satellite launches since 2000. So many have been launched, a comprehensive overview is beyond the scope of this limited article. Here are a couple of highlights:

The last of the big Phase 3 satellites, AO-40, was built by an international team and launched from French Guyana on November 16, 2000. In December, an explosion onboard AO-40 shut the satellite down. Restoration from the ground began in earnest, and the team was able to get the satellite back online on Christmas Day 2000. It was operational until March 2004 when a final failure of the satellite occurred.

Since then, most (but not all) ham radio satellites have been low-Earth-orbit cubesats, a 10-cm cube with transponders and antennas, usually coupled with a project from a university or other learning institution.

SO-50 is an FM satellite launched by Saudi Arabia in 2002. It remains active today.

AO-51 was launched in 2004 by AMSAT North America. It had an FM repeater with both 2 meter and 1.2GHz uplinks and 70cm and 2.4 GHz downlinks. It also had a functioning bulletin board system (BBS) and a 10-meter PSK uplink. It was loud and easily workable. It ceased operation in November 2011.

India launched its first satellite, ­VO-52, in 2005. Weighing in at 93 pounds, it had two transponders and was capable of SSB/CW and FM operation. A very popular satellite, its batteries failed in 2014 after nearly ten years of service.

Chinese AMSAT (CAMSAT) has had several high-profile launches with their XW-series of six SSB/CW satellites in 2015 and their CAS-4 duo in 2017. As of this writing, only two of the six XW satellites are still functioning. Both CAS-4A and 4B are operational. All are easy to work. Several CAMSAT satellites are in the works, with launches scheduled for this year.

Diwata-2, or PO-101, was launched in 2018 at the Tanegashima Space Center in Japan. This FM satellite originated in the Philippines and remains active today.

In what may be a vision of the future, the Qatar Amateur Radio Society, along with AMSAT-DL in Germany, developed amateur radio payloads for use aboard the commercial satellite Es’hail 2, or QO-100, a geostationary satellite with a 2.4 GHz uplink and a 10 GHz downlink. While it doesn’t cover North America, it provides a constant satellite link from Brazil, across Europe and the Middle East, all the way to Thailand.

In recent years, AMSAT has had a series of launches with their FOX program with AO-85, 91, 92, and 95. These FM cubesats have had varying degrees of success, but all provided valuable information for the next phase of AMSAT’s productivity, the GOLF (Greater Orbit, Higher Footprint) program. Both FOX and GOLF are part of a long-range plan to get a sophisticated ham radio satellite back in high-Earth orbit.

This short history of ham radio satellites barely scratches the surface. I encourage you to read the following sources for a more comprehensive understanding of this incredible aspect of amateur radio. These sources listed provided the bulk of information for this article.

A Brief History of AMSAT from AMSAT’s website.

The Extraordinary History of Ham Radio Satellites by Space Today Online.

Sounds from Space from Matthias Bop, DD1US. An incredible library of recordings from many ham radio satellites over the years.

OSCAR 1: The First Amateur Radio Satellite

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