START 1960s 1970s 1980s 1990s 2000s THE FUTURE HAMSAT LAUNCHES NAMES FREQS ARISS MIR SAREX PACSATS

The blossoming interest among amateur radio operators around the world in building and sending hamsats to orbit flourished in the 1990s. In the early years of the decade, 21 amateur radio and amateur-related satellites were launched with another 18 planned for the latter part of the 1990s. The first year of the decade, 1990, was a record launch year. Eight hamsats were blasted to space that year -- a tie with 1981 for the most amateur radio satellites launched in one year. Close behind was 1991 with four amateur radio satellites and eight amateur-related satellites launched. Here is a summary in chronological order of more than two dozen amateur radio communications and science satellites, and amateur-related satellites, launched in the 1990s:

Microsats

The 1986 shuttle Challenger explosion caused a temporary shortage of spaceflight opportunities for satellite makers around the world. Competition from commercial satellite owners for space aboard rockets meant amateur radio satellites, which had received many free rides over the years, would have to pay for some future launches.

Like civilian and military satellites, OSCARs had been getting heavier and larger. Smaller satellites would fit in places on rockets reserved for lead ballast and would need only modest launch services. The answer for amateur radio would be a radical design departure-microsatellites.

AMSAT's new standard spacecraft would be very small in size and weight, making possible cheap launches. Each microsat was to be so compact and lightweight it could be launched to orbit by even the smallest space booster.

The microsats could fit where larger satellites couldn't, making more launch opportunities available. They were even smaller than payloads designed for NASA shuttle GAScans.

Amateur satellite designers couldn't command vast budgets, supercomputers and thousands of technicians like major aerospace firms. Instead, the volunteer radio amateur community went back to its experimenter roots and showed that back-of-the-envelope designs could be turned into state-of-the-art spacecraft.

AMSAT received an opportunity in 1989 to show off its new technology when the European Space Agency needed to test a new payload carrier.

ESA had a new piece of hardware called ASAP-Ariane Structure for Auxiliary Payloads-which was a large flat ring to hold small satellites at equal distances around its level surface. The idea was to give small secondary payloads inexpensive rides to space alongside major satellites.

To test the new structure, AMSAT and UoSAT built six small amateur radio satellites for a free ride to space on an ASAP aboard an Ariane flight.

The six microsats launched January 22, 1990, to 500-mi.-high polar orbits were:

• UoSAT-OSCAR-14 (UO-14) from Surrey,
  
  
• UoSAT-OSCAR-15 (UO-15) from Surrey,
  
  
• AMSAT-OSCAR-16 (AO-16) from North American AMSAT,
  
  
• DOVE-OSCAR-17 (DO-17), also called Peacetalker, from Brazilian radio amateurs,
  
  
• WEBERsat-OSCAR-18 (WO-18) from Weber State University, and
  
  
• LUsat-OSCAR-19 (LO-19), from Argentine radio amateurs.

Microsats shared a standard framework design, but each was outfitted with electronics suited to its particular mission. Compared with the massive proportions and tonnage weights of civilian and military communications satellites, the pee-wee microsats were nine-inch cubes under 25 lbs. each.

AO-16, DO-17, WO-18 and LO-19 were designed at Boulder, Colorado, and other cities in the U.S., Argentina, Brazil and Canada, by AMSAT-North America, AMSAT-Argentina, BRAMSAT (AMSAT-Brazil) and the Center for Aerospace Technology (CAST) at Weber State University, Ogden, Utah. AMSAT volunteers at the Microsat Lab in Boulder assembled their own AO-16 as well as DO-17 for BRAMSAT, WO-18 for Weber, and LO-19 for AMSAT-Argentina.

The hamsats were shipped to the European Space Agency launch site in French Guiana where they were attached to the ASAP.

The six ended up in nearly-perfect Sun-synchronous orbits passing over local areas at about the same time each morning and evening.

The six were the largest number of Western hamsats sent to space at one time. It was the biggest single proliferation since 1981 when USSR hams had sent up six in one flight. Here's the story on each of the microsats:

1990: UoSAT-OSCARs 14 and 15

By the end of the 1980s, University of Surrey space enthusiasts had a complex new satellite, UoSAT-C, ready to go to space. In fact, it was scheduled for launch in 1988 on a U.S. rocket, but the flight was postponed. The UoSAT team wasn't able to locate a ride to space for the heavy UoSAT-C, but they did obtain a launch for a pair of lighter satellites on the Ariane ASAP test.

Due to ASAP weight limits, the functions of UoSAT-C had to be split between two lighter replacement satellites-UoSAT-D and UoSAT-E.

Fortunately, UoSAT-C had been loaded with modules which could be pulled apart quickly to take advantage of the short-notice Ariane opportunity. Many mechanical and electrical parts of UoSAT-C were taken apart and reassembled. The UoSAT-C framework was shelved.

UoSAT-D and UoSAT-E were matching frameworks outfitted with identical housekeeping computer systems, but otherwise housing different electronic payloads. They would be low-orbit pacsats with message handling. They would study space radiation and its effects on semiconductors, develop a low-cost computerized spacecraft attitude control for precise Earth pointing, and photograph Earth with a low-cost charge-coupled device (CCD) television camera.

UoSAT-D and UoSAT-E were attached to the ASAP and launched January 22, 1990, alongside the four AMSAT microsats.

UoSAT-D was renamed UoSAT-OSCAR-14 (UO-14). It also has been called UoSAT-3.

UoSAT-E was renamed UoSAT-OSCAR-15 (UO-15). It also has been called UoSAT-4.

Surrey hams successfully commanded UO-14 and UO-15 on during their first day in space. Later that day, each spacecraft's computer software was sent up by radio to the satellites. Nominal telemetry was received from both hamsats.

Unfortunately, news turned bad 25 hours later when no UO-15 signals were received at Surrey.

Operators repeatedly transmitted commands to activate its redundant systems, with no luck. They tried for months to hear something, but no signals have been received since then from UO-15.

Stanford University had helped Surrey back in 1982, transmitting a strong signal to UO-9 to overcome blockage of that satellite's command receiver. Stanford hams tried again in 1990 to come to the rescue, using the same 150-ft. antenna with sophisticated digital signal processing equipment to look for an extremely weak signal from UO-15 oscillators. The big dish was able to hear UO-14 oscillators, but nothing from UO-15.

Attempts to restart UO-15 were abandoned. U.S. government radar continues to track the satellite, orbiting a mile or so higher than UO-14, amidst the pack of microsats launched January 22, 1990. UO-15 is simply dead in orbit.

The loss of UO-15 was mitigated by the good news from UO-14 which worked well. The tragedy spurred UoSAT to build a new small satellite, UoSAT-F, which was launched in 1991.

Meanwhile, UO-14 was working well in orbit handling lots of electronic-mail messages.

UO-14 has three computers for housekeeping and packet radio, including a 16-bit microprocessor with 4.5 megabytes of RAM. Four megabytes are used for bbs message storage.

The satellite's digital transponder receives at 145 MHz and transmits at 435 MHz. Ten watts of transmitter power make the satellite usable by small portable ground stations. Telemetry data packets are beaconed near 435 MHz.

UO-14 is an Earth-pointing satellite with a gravity-gradient boom and computer-controlled magnetorquing, an ideal system for small satellites in low-Earth orbit because it has no continuously-moving parts and expends no fuel.

To calculate its attitude, UO-14 carries a flux-gate magnetometer measuring Earth's geomagnetic field in the satellite's three axes.

Electricity is generated by gallium-arsenide solar arrays feeding nickel-cadmium rechargeable batteries. The satellite rotates slowly, distributing the Sun's light and heat evenly across the satellite.

Pacsats regularly relay messages around the globe to terrestrial packet networks in many regions. A gateway is a satellite ground station acting as a bridge between a pacsat and a terrestrial network. Automated gateways upload and download traffic without human operators.

In 1991, radio amateurs in Alaska and California created a gateway offering same-day delivery of dozens of messages to Alaska from the Lower 48 states. That success brought gateways to every continent. Today, scores of gateways cover North and South America, the Caribbean, Europe, the Middle East, South Africa, Oceania, Asia and even Baffin Island above the Arctic Circle. They deliver messages and responses within 24 hours. Such fast action is important in health-and-welfare traffic during emergencies and natural disasters.

In 1992, the first medical image transmitted via hamsat showed a fractured hip repaired with a compression hip screw. The hip had been pictured by a portable fluoroscopy X-ray displaying real-time images on a TV monitor for a physician during surgery. The image was stored on computer disk and transmitted to UO-14. The satellite kept it in memory for a few days, then sent it back to Earth, proving hamsats can help remote clinics get assessments from specialists.

Some of the construction costs of UO-14 had been paid by an American organization known as Volunteers In Technical Assistance. The non-profit organization had a large library of data on farming, windmills, stoves, ovens and other useful non-military subjects which it wanted to send to development workers in remote areas via UO-14's store-and-forward mailbox.

For a time, radio amateurs and VITA shared UO-14's transmitter, computer and 400-message memory. To accommodate both amateur and non-amateur users, the satellite switched back and forth between amateur and non-amateur frequencies.

When UO-14 transmitted on its non-amateur frequency, it was sending technical information to areas of the developing world poorly served by existing data communications. Such traffic was considered inappropriate for amateur channels. When the transmitter switches occurred, amateurs lost reception from their satellite for periods from a quarter-second to five seconds.

UO-14's uplink became congested with users. When 200 stations began using the satellite regularly, the satellite's 400 message limit was reached frequently. Amateur stations were limiting access for non-amateur VITA stations. After the British hamsat UO-22 was launched in 1991, Surrey decided to change UO-14's mission.

Amateur radio service was dropped. UO-14 stopped transmitting on its amateur frequency. Ham operations were moved to the new UO-22.

Today, UO-14's electronic mailbox links VITA with inexpensive, portable ground stations built around a computer, radio, battery and antenna. A ground station fits in a suitcase and works where no power lines exist. The pacsat is low enough for small ground stations to use simple whip antennas, made from coat hangers if necessary, to hear the satellite.

UO-14's bbs memory holds four million characters of information. When the satellite is overhead, a ground station can send up a message at 500 characters per second. During the few minutes the satellite is overhead, a ground station might send up 200,000 characters of information-equivalent to ten magazine articles.

Even if mail were picked up immediately by a recipient the next time the satellite passed over his head, it might be stored in the satellite from a few seconds up to twelve hours. Mail can stay in the satellite for days, of course, awaiting radio commands from an addressee.

A busy operator on the ground can put his satellite station on autopilot. He programs his computer to determine when the satellite will be overhead. Most pacsats pass over the North and South Poles every hour and a half and over any one point on the surface four times a day. One is overhead for only a dozen minutes or so.

At the appointed hour, the ground-station computer would fire up its radio and send up a signal asking the satellite if any messages were on hand. If messages for that ground station were stored in the satellite, the satellite's computer would order them sent down.

The computer on the ground then could store them for future reading and turn off its radio as the satellite passed out of sight over the horizon.

A pacsat like UO-14 and others makes it cheap and easy to send messages, data and images in or out of developing regions. Scores of portable ground stations already are linking underdeveloped countries to medical, weather, agriculture and engineering databanks.

Volunteers in Africa, Asia and South America use portable ground stations to ask for technical assistance. Travelers in the most rugged terrain receive data. Relief workers communicate directly with emergency teams at natural disaster sites.

1990: AMSAT-OSCAR-16

Among the microsatellites launched January 22, 1990, was a small spacecraft known before launch as PACSAT-NA and after launch as AO-16 for AMSAT-OSCAR-16.

AMSAT ground controllers had no trouble commanding AO-16 on the air shortly after launch. The packet telemetry beacon was strong enough to be received easily with handheld radios using small, flexible, rubber-covered antennas. The message bbs was turned on in March 1990.

AO-16 downlink frequencies are near 437 and 2401 MHz. Uplink frequencies are near 145 MHz. Four packet stations on the ground can use the AO-16 bbs at one time.

The medical image of a fractured hip transmitted via UO-14 in 1992 also was relayed by AO-16. The Alaska-to-California message-traffic gateway created in 1991 used AO-16.

1990: DOVE-OSCAR-17

DOVE Peacetalker may be best known among the microsats launched in January 1990. It certainly has had the largest listening audience.

After launch to a low polar orbit alongside the other small satellites, DOVE Peacetalker was renamed DOVE-OSCAR-17. DOVE stands for Digital Orbiting Voice Encoder.

DO-17 was designed to educate the public about space by providing an easily-received satellite signal for demonstrations to children. DOVE was the first hamsat to transmit spoken messages promoting peace among nations.

The microsat has a digital recording system hooked to its receiver and a voice-synthesizer attached to its transmitter. School children around the globe are encouraged to write and speak messages which are transmitted to DOVE by Brazilian hams. DO-17 records the voices and then broadcasts the messages on 145.825 MHz to be heard by anyone with an inexpensive vhf fm receiver or vhf scanner radio of the kind used to monitor police and fire calls.

The satellite offers students easy access to space research data. Its voice is programmed with various languages so students around the world can understand and learn as DOVE reads out data from the satellite's sensors in synthesized speech.

No tracking is required to receive DO-17. Its signals have been received using a standard pull-up whip antenna attached to a receiver or a flexible antenna on a portable receiver. A high outdoor antenna is even better than an indoor antenna.

Listening from 8 am to 1 pm and 7 pm to 12 midnight local time may reveal the microsat flying overhead several times. When its 145.825 radio is on, it transmits for 2.5 minutes followed by an off period of 30 seconds during which it stands by for commands from the ground.

DOVE has beacons, but no active transponders. Besides 145 MHz, there is an S-band beacon relaying data in packet radio near 2401 MHz.

Many high schools collected telemetry data for science experiments. One California physics class monitored the rate at which DO-17 was spinning. It was supposed to be about three revolutions per minute (rpm). Analyzing telemetry sampled at intervals, the students understood the relationship between sample rate and spin rate. If the sample rate weren't fast enough, incorrect conclusions would have been drawn about rate and direction. Students concluded DOVE's spin rate had slowed.

A teacher's guide to using DO-17 with classroom exercises and experiments is available to schools from AMSAT Science Education Advisor, 421 N. Military, Dearborn, Michigan 48124 USA.

1990: WEBERsat-OSCAR-18

Say "cheese" when you look up; you may be looking into the business end of a hamsat camera. WEBERsat-OSCAR-18, designed at Utah's Weber State University, has been snapping photos of Earth since shortly after it was lobbed to a 500-mi.-high polar orbit alongside the other AMSAT microsats on January 22, 1990.

WO-18 has a charge-coupled device (CCD) television camera which stores images in memory and compresses them into packet radio bursts transmitted to Earth.

One picture fills about 200k of computer memory, but the hamsat can send it down to the WSU ground station in as little as seven seconds.

WO-18 has recorded such exotic locales as Ethiopia, the Bay of Bengal, Brazil, Africa's Lake Victoria, clouds over the Indian Ocean, Chile, the coastline of British Columbia near Vancouver Island, Australia, India, the coast of Peru, the U.S. Great Lakes, even the Moon, Sun and stars.

Wispy clouds in WO-18 pictures mark the possibility of satellite meteorology with very inexpensive imaging equipment.

WO-18 has a message bbs, a particle impact detector, a spectrometer, a magnetometer for navigation, an amateur television (atv) uplink receiver, and two downlink beacon transmitters.

1990: LUsat-OSCAR-19

AMSAT-Argentina had been contemplating a satellite of its own in 1988 when news of the six-payload Ariane ASAP launch became known. The Argentines immediately joined North American AMSAT in the microsat project.

The letters LU are an amateur radio callsign prefix for Argentina so the satellite was dubbed LUsat. It was licensed in Argentina and paid for by Argentines, but constructed in Utah at CAST.

In orbit, it was renamed LUsat-OSCAR-19. Commanded in space from Argentina, LO-19 is a pacsat with digital message bbs available for non-profit use by hams around the globe.

The first message sent to the bbs was from Carlos Saul Menem, president of the Argentine Republic and a ham operator himself.

One special telemetry beacon aboard LO-19 transmits data about the hamsat in easy-to-read 12 words-per-minute Morse code at 437.125 MHz. LO-19 broadcasts news bulletins continuously on Mondays on another frequency near 437 MHz.

LO-19 and other hamsats relayed essential public-service communications after Hurricane Iniki leveled parts of Hawaii in 1992. Health and welfare messages from devastated areas were forwarded to anxious relatives around the globe.

1990: Fuji-OSCAR-20

Japanese hams had a replacement satellite ready three months after their first had to be turned off in 1989 for lack of electricity.

Their first hamsat had been called Japan Amateur Satellite (JAS-1a) and Fuji-OSCAR-12. Fuji is Japanese for wisteria. The replacement was labeled JAS-1b and called Fuji-OSCAR-20.

JAS-1b was the seventh hamsat hurled to space in 1990. Just 16 days after the European Space Agency launched the microsats, an H-1 rocket provided by Japan's National Space Development Agency ferried the 110-lb. JAS-1b to a 750-mi.-high orbit February 7. The H-1 also carried two government satellites, MOS-1b and Debut. It was the first time Japan had launched more than two satellites at one time.

Eclipses kept FO-12 from producing enough electricity, but FO-20 was in a more favorable orbit without as many periods of solar eclipse.

FO-20 uses torque generated by interaction of two permanent magnets with Earth's magnetic field to maintain its attitude.

FO-20 receives and retransmits voice and Morse code, permitting hams to chat over wide areas of the globe. It also provides an electronic mailbox, storing messages in 1.5 megabyte random-access memory (RAM) and delivering them on request to other stations at later times. Amateurs on one side of the world place messages on the satellite's electronic bulletin board to be read by others when the hamsat is on the far side of the globe.

The communications uplink is near 145 MHz. The downlink is near 435 MHz. Telemetry is in Morse code and packet radio near 435 MHz.

1990: Badr-1

Radio amateurs have pushed the state of the art in electronics in nations around the globe. In Pakistan, for instance, a number of engineers at the government's Space and Upper Atmosphere Research Commission (SUPARCO) are hams.

SUPARCO is at the University of the Punjab at Lahore, a prominent border city in eastern Pakistan not far from Delhi, India, and at the Arabian Sea port of Karachi in southern Pakistan. SUPARCO has fired small rockets on sub-orbital science flights from launch pads at its Maini Beach flight-range, 36 miles west of Karachi.

Several SUPARCO personnel completed masters degrees in engineering at England's University of Surrey-the institution which built and operates UO-9, UO-11 and UO-22 hamsats. While at Surrey, they worked on UoSAT projects. When the engineering students returned to Karachi and Lahore, they built ground stations and took part in digital communications experiments with the British hamsats UO-9 and UO-11.

SUPARCO hams also used knowledge gained at the university to build their own satellite. With support from the Pakistan Amateur Radio Society, they started building a small hamsat in the last half of 1986. They called it Badr, after the Urdu language word for "new moon."

The first satellite, Badr-1 or Badr-A, was to have been ferried to space in a U.S. shuttle, but that plan changed after the 1986 Challenger explosion delayed American flights.

Four pre-launch ground tests were successful. In 1989, Pakistan registered the planned satellite with the International Frequency Registration Bureau. Then the spacecraft was shipped to China's Xichang Launch Center in 1990.

China launched the 150-lb. Badr-1 on July 16, 1990, to a 375-mi.-high circular orbit on a Long March rocket. It was one of the eight hamsats sent aloft in 1990. The tiny Badr-1 circled the globe every 96 minutes, passing over Pakistan for 15 minutes three to four times a day.

The Pakistani satellite, shaped as a polyhedron with 26 surfaces or facets, was about 20 inches in diameter. It resembled the U.S. NUsat launched from an American shuttle in 1985, but Badr-A housed digital communications gear modeled after the radio system aboard the British satellite UO-11 launched in 1984.

Badr-1 offered one radio channel for digital store-and-forward communications. Uplink was near 435 MHz. Downlink was near 145 MHz. The telemetry beacon was near 145 MHz.

Badr-1's orbit was so low it could not sustain itself in space more than 146 days. It fell into Earth's atmosphere and burned December 9, 1990.

SUPARCO hams built a second satellite, Badr-2, to be launched in 1994-95. Badr-2 will be more sophisticated than Badr-l, with a CCD camera for pictures of Earth and a system allowing ground stations to change the hamsat's direction in space.

1991: AMSAT-OSCAR-21 / RADIOSPUTNIK RS-14

It could have been just another amateur radio package riding piggyback on a big government spacecraft when it was launched in 1991. But, when ground controllers converted AMSAT-OSCAR-21 into a voice repeater in the sky in 1992, it immediately became one of the most popular hamsats orbiting the globe.

The Russian satellite had been called Radio M-1 as it rode to space from Russia's Northern Cosmodrome at Plesetsk on January 29, 1991.

Like those popular Russian dolls inside dolls, Radio M-1 was inside a large government spacecraft called INFORMATOR-1, which housed equipment from the Ministry of Geology and Science (GEOS). And then, inside Radio M-1, was a German digital transponder called RUDAK-2.

The Russian space industry had been in the habit of labeling improved spacecraft with the letter M for modified. For instance, when the Progress space freighter was redesigned, it was called Progress-M. Similarly, after the first hamsats had been called Radio-1 and Radio-2, the fourteenth was modified and called Radio M-1.

RUDAK is a German-language acronym for Regenerating Transponder for Digital Amateur Communications. RUDAK-2 was designed and built by amateur radio members of AMSAT-DL, the German affiliate of AMSAT. DL is Germany's amateur callsign prefix. RUDAK-1 had flown to space aboard AO-13, but didn't work.

The Russian amateur radio satellite club Orbita and the Adventure Club of Moscow built Radio M-1 as a joint project with German hams at Marburg, Munich and Hannover. The collaboration led to dual names for the new amateur radio satellite once it arrived in orbit: AMSAT-OSCAR-21 (AO-21) and Radiosputnik-14 (RS-14).

AO-21/RS-14 is in a 600-mile-high circular orbit. Its spacecraft-mate, the geological-survey satellite GEOS, should not be confused with the American GOES weather satellites. The combo is orbiting Earth every 104 minutes.

Amateur radio operators around the world use AO-21/RS-14 to communicate via frequency modulation (fm) voice, single-sideband (ssb) voice, Morse code (cw) telegraphy, and packet radio. RUDAK-2 is the packet-radio section of AO-21. A portion of computer memory is set aside as a mailbox where hams leave messages for others.

In 1992, ground controllers switched RUDAK to an fm repeater mode. It immediately became very popular with hams around the globe because it was very easy to use common ham gear with simple antennas to access the repeater in the sky. The uplink frequency was near 435 MHz. The downlink was at 145 MHz.

Non-human voices were heard from AO-21 in 1991 as ground controllers tested its talking-satellite experiment. The 145 MHz telemetry beacon was transmitting, "I am completely operational and all my circuits are functioning properly." The multilingual hamsat spoke Russian in 1992 when the speech synthesizer was greeting, "Hello to those on the ground and the cosmonauts in the space station Mir."

A Russian-Danish expedition, organized by the Adventure Club of Moscow, one of the original sponsors of AO-21, discovered the burial place of Danish explorer Vitus Bering (1682-1741) and his eight-man team at Commander Bay in 1991.

In 1728, the Danish navigator had been the first to traverse what we now know as the Bering Strait. He died in 1741 on Bering Island in the Commander Islands east of Kamchatka Peninsula in the Bering Sea.

A 1992 ceremony to re-bury Vitus Bering was held on his island. In honor of the event, AO-21's digital voice broadcast, "Greetings to the Russian-Denmark Expedition, which discovered the burial place of Vitus Bering and his team at the Commander Bay near Kamchatka."

Also in 1992, a female voice was heard on the AO-21 downlink speaking in the Slovenian language, the native tongue of Matjaz Vidmar, who was listening to a portable ham transceiver in his hospital bed. He was hospitalized following an automobile accident. Vidmar was known for his transponder designs, including S-Band transmitters for the hamsats AO-16, DO-17 and Phase-3D.

Celebrating the annual Army-Navy football game in 1992, Naval Academy midshipmen ran from Annapolis, Maryland, to the stadium at Philadelphia, Pennsylvania. They carried an unusual football helmet outfitted with a global-positioning satellite (GPS) receiver and a packet-radio satellite terminal which reported their positions along the route every two minutes. From 600 miles overhead, the hamsat AO-21 helped out along the way by relaying position reports from runners and chase vehicles.

1991: Radiosputniks 12 and 13

RS-10 and RS-11 worked very well after their 1987 launch and were popular with amateur satellite enthusiasts. Sticking with a proven design, Russian hams delivered another popular package February 5, 1991, in the launch of RS-12 and RS-13, just a week after AO-21/RS-14.

It was another flashy three-in-one space shot-the hamsats Radiosputnik-12 and Radiosputnik-13, and the government navigation satellite Cosmos 2123, all combined in one large spacecraft orbiting 600 miles above Earth.

Hamsats often ride piggy-back to space on government rockets, but there they separate into different orbits. By comparison, Cosmos 2123, RS-12 and RS-13 are one package with ham radio gear taking electricity from Cosmos' solar-panel wings. Cosmos 2123 helps Russian fishing fleets locate themselves on the world's oceans.

As with all hamsats since 1961, the Radiosputnik series is open for use by all amateurs around the globe. RS-12 and RS-13 telemetry beacons are near 29 and 145 MHz. They have identical transponders, but frequencies differ. Ground stations transmit on frequencies near 21 and 145 MHz. Downlink signals are near 29 and 145 MHz. Cosmos 2123 transmits at 150 MHz.

An innovation of earlier Radiosputniks, the popular autotransponder "robot" operator, was carried forward in RS-12 and RS-13. Hams also have fun sending slow-scan television (sstv) pictures to each other via RS-12 and RS-13.

1991: UoSAT-OSCAR-22

For the first time ever, on July 17, 1991, thirteen OSCARs were active in orbit at one time. They were AO-10, UO-11, AO-13, UO-14, AO-16, DO-17, WO-18, LU-19, FO-20, AO-21/RS-14, the RS-10/RS-11 combo, the RS-12/RS-13 combo and the brand-new UO-22.

Hams at the University of Surrey had designed and built yet another small satellite, UoSAT-F, which was launched that July 17 on a European Ariane rocket. In polar orbit, 480 miles above Earth, UoSAT-F was renamed UoSAT-OSCAR-22. It also was known as UoSAT-5.

Some of the costs of UO-22 had been borne by the organization SatelLife, formed by International Physicians for the Prevention of Nuclear War, an organization which had received a Nobel Peace Prize in 1985.

SatelLife used the pacsat to start HealthNet, an international not-for-profit E-mail network for health professionals. Early users included five African medical schools which linked up with HealthNet to receive fresh medical literature and exchange electronic mail by satellite.

HealthNet message packets were transmitted on non-amateur frequencies near 428 MHz, not far from UO-22's amateur downlinks at 435 MHz. When off-duty from HealthNet, UO-22 would switch to amateur radio frequencies.

In congestion very similar to the UO-14 overcrowding problem, hams using UO-22 were limiting access for non-amateur SatelLife stations even as the non-amateur transmissions interrupted amateur activity. Surrey had obligations to SatelLife and VITA, so it moved to resolve the congestion in 1992.

Amateur radio service was dropped from UO-14 altogether in favor of non-amateur SatelLife and VITA and all ham activity was moved to UO-22. Today, UO-22 works for radio amateurs while UO-14 works for SatelLife and VITA.

UO-22 is a pacsat with bbs, but the satellite's most remarkable feature may be its charge-coupled device (CCD) television camera with 110-degree wide-angle lens showing a field of view nearly the same size as the satellite's footprint.

UO-22 snaps three or four shots a day, each of a ground area 994 by 1118 miles. Notable pictures have included Italy, showing the familiar boot outlined by the Mediterranean, Adriatic, and Tyrrhenian Seas, and Yugoslavia and Greece; an Antarctic iceberg; Bulgaria and Romania; Denver; Cuba and Haiti; Denmark and the Netherlands; haze over Djibouti, Somalia and Yemen; French Guyana; eastern South Africa; Egypt and Sinai, the Nile Valley and the Upper Nile; the Gulf of Mexico; Equatorial Africa; Kuwait and Persian Gulf smoke plumes; Limerick, Ireland; the Balkans; North Africa; the Great Lakes; northern Australia; Florida and the Mississippi Delta; Spain, Portugal and Mahgreb; California; the Red Sea; Korea; and the Straits of Hormuz.

The 110-lb. hamsat also carries radiation dose experiments, horizon sensors, and magnetometers, one inside and the other on a small boom protruding above the spacecraft. UO-22 has a 15-ft. gravity-gradient boom with a five-lb. weight on the end which provides restoring torque to keep the camera lens and radio antenna pointed to Earth.

Her Majesty Queen Elizabeth II was touring the UoSAT control room in 1992 when UO-22 flew overhead and transmitted a synthesized-voice greeting. Then another hamsat, UO-14, delivered a message to Her Majesty from President Fredrick Chiluba of the Commonwealth nation of Zambia. The Queen left a reply message which was returned to Zambia by UO-14.

1992: KITsat-OSCAR-23

As it had done in 1990, amateur radio led a nation into space again in 1992. Back in 1990, it had been Pakistan's first-ever satellite. This time, it was South Korea's first-ever satellite.

The microsat was built at Great Britain's University of Surrey for the Korean Advanced Institute of Science and Technology (KAIST) by ten Korean students working under the guidance of Surrey engineers. The 110-lb. South Korean hamsat was called KITsat-A.

A European Ariane rocket put KITsat-A into orbit on August 10, 1992. AMSAT called the satellite KITsat-OSCAR-23 (KO-23).

Its builders named the hamsat Uribyol, Korean for "Our Star." Uribyol No. 1 made South Korea the 22nd country with a satellite in orbit since 1957 when the USSR launched the first Sputnik.

KO-23 consolidated technical advances from Surrey's UO-14 and UO-22, cloning much of its electronics from UO-14, UO-15 and UO-22, shoe-horning them into the same tiny UoSAT style of spacecraft "bus." It's a 14-in. cube with an 18-ft. gravity-gradient boom made of measuring-tape steel preformed so it extends from the spacecraft to form a tubular shape. A five-lb. weight is on the end. The boom provides restoring torque which keeps the TV camera lens pointed towards Earth.

KO-23's inclination of 66 degrees makes it available to users farther north and south than most amateur radio satellites. It circles Earth every 112 minutes. KO-23 circles Earth a dozen times a day, passing over the Korean peninsula seven times a day. The small satellite is photographing Earth, detecting cosmic particles and measuring cosmic rays, and providing an amateur radio electronic-mail system in orbit. It also makes digital voice-broadcast tests.

Spacecraft in orbit are showered by radiation from beyond Earth, which can damage integrated circuit (IC) chips and scramble data stored in solid-state memories. AO-10 and FO-12 were crippled by radiation damage. Recent hamsats have used even-more-delicate semiconductors in critical systems. UO-9, UO-11, UO-14 and UO-22 began amateur studies of radiation, measuring effects on electronics. However, those measurements were in relatively-benign low-altitude, high-inclination orbits. On the other hand, KO-23 is in a high-altitude, low-inclination orbit, where much worse radiation is found.

KO-23 has a cosmic ray experiment looking for high-energy cosmic rays and measuring the total radiation dose. Effects on computers, memories, power systems and solar panels are monitored.

KO-23 is a pacsat with two user uplink frequencies in the 145 MHz band, one 435 MHz transmitter, and a command uplink. It was the second amateur radio satellite to offer high-speed 9600-baud transfers. For message storage, the pacsat has 13 megabytes of CMOS random-access memory (RAM).

KO-23 has speech synthesis, store-and-forward speech relay, and high-speed modulation. It allows users to leave voice mail. KO-23 was reported playing military-style music in November 1992.

KITsat has an upgraded version of the UO-22 TV camera capable of shooting photographs with either four-kilometer or 400-meter resolution.

Like UO-22, one of KITsat's two CCD cameras provides a wide field of view with four-kilometer ground resolution. However, it covers a larger area of Earth than UO-22's camera. KITsat's second camera has a telephoto lens giving 400 meters ground resolution. The wide-angle camera is used to spot areas to be photographed in more detail. Then, detailed images are made with the narrow-field camera. Pictures snapped by KO-23 are stored as data in memory, to be downloaded by ground stations via packet radio.

KO-23 has recorded remarkable images around the globe, including Antarctica and the tip of Patagonia as a low Sun angle highlighted splendid cloud formations; wide-angle shots of Korea and Japan; telephoto shots of Kitakyushu, Hiroshima and the land bridge between the Japanese islands of Kyushu and Honshu; and the coastline of Burma, Laos, Thailand, and Bangladesh.

Please note: the history of the 1990s is under development

Hamsat Chronology.

Well, that's the extraordinary story of amateur radio satellites so far. What will happen in the 21st century? More hamsats:

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