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 Previous: Vanity Processing to Resume this Week! |  Next: New Mexico Becomes 14th State to Adopt PRB-1 Legislation |
By Anthony R. Curtis, K3RXK
Contributing Editor
March 6, 2002
The US conducted the first-ever launch of eight satellites on one rocket on March 9, 1965. Most were military spacecraft, but one was extraordinary--not only in Amateur Radio history but in the general history of space satellites. The small craft known as OSCAR 3 was the first-ever real-time repeater satellite and the first active telecommunications satellite with free access to users around the world.
 During OSCAR 3's final checkout, Lance Ginner, K6GSJ, tests the satellite while a two-tone test signal is radiated by a test generator on the bench. Before integration, the meter panel was removed and a flight panel substituted. |
Why do we call our satellites OSCAR? Because the first four Amateur Radio satellite projects that flew in 1961-1965 were managed by pioneering hams in a US West Coast group known as Project OSCAR--an acronym that stands for Orbital Satellite Carrying Amateur Radio. AMSAT, the Radio Amateur Satellite Corporation, was formed in 1969, by an East Coast group wanting to build and fly hamsats.
Radio amateurs around the globe had been riveted by the beep-beep signal from Sputnik in 1957. The idea that would grow into Project OSCAR began in 1959, when Don Stoner, W6TNS (SK), wrote about a ham satellite in CQ magazine. He asked if any reader could find a rocket ride to space for a solar-powered 6-meter to 2-meter transistorized repeater that was being tested at the time for balloon trials over the American Southwest.
One reader, Fred Hicks, W6EJU, knew something about rockets and space launches. He had worked for a missile contractor and had observed six satellite launches. When he and Stoner got together, Project OSCAR began to gel out of their collective Amateur Radio imaginations. Hicks became chairman of the Project OSCAR Association in California.
In September 1960, Hicks, Stoner, an ARRL representative and the head of the Jet Propulsion Lab's Space Instrumentation Section came up with a two-part plan. First, a beacon transmitter would be designed, built and launched. Then an orbiting repeater would be sent up.
The ARRL endorsed Project OSCAR, and in May 1961 QST started a series of articles informing operators about the imminent launch of OSCAR 1. Many were written by Ray Soifer, K2QBW (now W2RS), among them "Space Communication and the Amateur" and "The Feasibility of Amateur Space Communication."
In 1961, Stoner wrote in QST that a US satellite with a remote-control transceiver stimulated the West Coast hams. He said that, with the help of all 200,000 hams at the time, Amateur Radio would be able "to supply the scientific world with volumes of communication data gathered by observing and using the OSCAR satellite."
 Almost three years of effort ended in the successful operation of Amateur Radio's first repeater in space. (L-R) Al Horley, ex-9M2TC; Bill Orr, W6SAI (SK); Bill Eitel, W6UF (SK); Don Norgaard, W6VMH (SK); and Lance Ginner, K6GSJ. |
The radio electronics pioneer Orrin "Hank" Brown, W6HB (SK), recipient of the ARRL Merit Award, also was a founding member of Project OSCAR and a project leader for OSCAR 3. Nick Marshall, W6OLO (SK), was responsible for the design, development, testing and checkout of the first three OSCARS--assisted by Chuck Townes, K6LFH, and Lance Ginner, K6GSJ. Other hams involved in the first OSCARs included Gene Root, WB6OOO (SK), Chuck Smallhouse, WA6MGZ (now W7CS), Harley Gabrielson, K6DS, and EIMAC's Bill Eitel, W6UF (SK).
Marshall later was known for his Project OZMA work, which preceded SETI. Ginner went on to have a part in the launching of all Amateur Radio satellites (except Russian hamsats) through OSCAR 13.
 Lee Gray, K9AAJ (SK), of Quincy, Illinois, worked Ernest Renner, K2IEJ (SK), for the first US two-way QSO via OSCAR 3. |
How quickly can a satellite go from drawing board to orbit? Project OSCAR designed and built a 10-pound beeping space beacon they called OSCAR 1. The Air Force said it would ferry it to space aboard a rocket carrying a Discoverer satellite from Vandenberg Air Force Base in California.
In July 1961, the ARRL asked the US State Department to back the project. In September, Project OSCAR received that backing and approval of the FCC.
On December 12, 1961, Discoverer 36 rode a Thor-Agena rocket to orbit, carrying OSCAR 1 along as ballast. The little hamsat was dropped off in its own separate orbit.
That afternoon--60 years to the day after Marconi's Morse "s" transited the Atlantic to a hilltop in Newfoundland--hams heard OSCAR 1's Morse "HI" coming down from 290 miles above.
OSCAR 1's transmitter put out only 140 mW at 145 MHz--yet that was 14 times the power of the 10-mW radio transmitter used by America's first government satellite, Explorer 1, launched in 1958. As planned, OSCAR 1 did not carry a repeater. It simply sent "HI" in International Morse code over and over.
Project OSCAR's backup spacecraft became OSCAR 2, launched to an altitude of 240 miles six months later on June 2, 1962. Its transmitter power was lowered to 100 mW for longer battery life.
By the way, lost in the dust of history is another OSCAR built about the same time, with a 250-mW transmitter. It was not launched because Project OSCAR had moved on to its first satellite with a transponder. At the time, they referred to the satellite as OSCAR III (Roman numerals) and to the transponder as a translator.
OSCAR 3 was launched March 9, 1965, alongside seven US Air Force satellites aboard a Thor-Agena D rocket from Vandenberg Air Force Base, California, to an altitude around 575 miles.
The small 36-pound hamsat was a milestone in global satellite communications history. OSCAR 3 enjoyed several "firsts."
OSCAR 3's two-way signal-repeating transponder created a radio relay in the sky, with a receiver listening for uplink signals at 146 MHz and a 1 W downlink transmitter at 144 MHz. Interestingly, in comparison with today's practices, the voice-mode relay system was a 50 kHz wide linear transponder entirely within one ham band.
In addition to its transponder, OSCAR 3 had two radio beacons. One sent a continuous signal for tracking and propagation studies. The other sent telemetry data about temperatures and battery voltages.
A few solar cells were attached to the satellite to recharge the battery powering the beacons. However, the satellite was not fully solar powered. The solar cells allowed the beacons to continue transmitting months beyond the 18-day life of the transponder.
More than 1000 hams from 22 nations chatted via OSCAR 3 as it circled Earth 206 times during those 18 days. The first transatlantic ham satellite link was made. The hamsat also carried the first direct contacts with hams in Eastern European countries such as Bulgaria and the nation known at that time as Czechoslovakia. Other exciting DX firsts linked New Jersey with Spain, Massachusetts with Germany, and New York with Alaska.
Nine months later, OSCAR 4 was to be the first high-altitude Amateur Radio communications satellite and the first amateur satellite to have a partial launch failure--but that's a story for another time.
| Want
to read more about OSCAR 3? Here are some QST articles:
Gabrielson, H.C. "OSCAR III Report -- Communications Results," QST, December 1965, pp 84-89. McElroy, Gil. VE1PKD, "Keeping Track of OSCAR: A Short History Amateur Radio's Race for Space," QST, November 1999, pp 65-66. Orr, William, W6TNS. "The OSCAR III V.H.F. Translator Satellite," QST, February 1963, pp 42-44. Orr, William, W6TNS. "OSCAR III Orbits the Earth!" QST, May 1965, pp 56-59. Walters, Arthur. "OSCAR III -- Technical Description," QST, June 1964, pp 16-18. Walters, Arthur. "Making Use of the OSCAR III Telemetry Signals," QST, March 1965, pp 16-18. |
Editor's note: ARRL
Life Member Anthony R. Curtis, K3RXK, lives in Florence, Kentucky. He describes
himself as "a dc-to-daylight kind of guy"
interested in AMSAT, TAPR, ARES, HF, VHF, UHF, digital, CW, SSB, FM,
QRP, contesting, DX and emergency preparedness. Licensed since 1954, he
originally held the call sign W8TIZ. An Extra class op with a PhD in mass
communication, Curtis has written 72 books about space, astronomy, computers
and electronics. He is editor of Space Today
Online. Active as an ARRL field volunteer, Curtis served as Section
Emergency Coordinator for the Maryland-DC Section and as net manager for the
Maryland Emergency Phone Net. He now serves as an ARRL Educational Advisor and
a Great Lakes Division Assistant Director. He also has been president of clubs
and repeater associations. Curtis is dean for academic information services at
the Union Institute & University in Cincinnati, Ohio. He is a NASA Solar
System Ambassador and an Apple Distinguished Educator. Readers can contact Tony
Curtis via e-mail.
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