It was in November 2022 that the UK wing of AMSAT (Radio Amateur Satellite Corporation) launched what looked like an impossible challenge. An award was announced for the first amateur radio operator or ham who could, from anywhere in North America, establish two-way contact with another ham living in Europe or Asia or any place where the satellite QO-100 has coverage.
This was daunting because North America does not fall within the range or 'footprint' of QO-100, the first and only geostationary satellite (a satellite that moves along with the Earth and, therefore, seems fixed) for radio amateurs. It was jokingly said that it would have been easier for someone with a mobile phone to travel to Mars and connect with friends on Earth.
No one was willing to take up the challenge for over one and a half years. And then a UK-based independent IT consultant, Ravi Gopan, with roots in Thiruvananthapuram, flew across the Atlantic from Reading in the UK to the Canadian island called Newfoundland last week.
He carried his equipment -- a VHF Transceiver, a self-made Transverter to convert VHF signals and dish antennae -- to the extreme east of the island, to its capital city St John's. There he found a rental balcony overlooking the Atlantic at a place called Petty Harbour, where DC's highest-grossing film Aquaman was shot, and installed his wares.
North American challenge
QO-100, placed right above the African Continent, covers the whole of Africa, East Europe, the United Kingdom, West Asia, India, half of China and Russia and the eastern projection of South America that includes Brazil. Except for a portion of Greenland, the entire North American continent – Mexico, the United States of America and Canada – is out of QO-100's horizon or coverage area.
As a consequence, hams in New York or Washington or Toronto or Mexico City are not able to use the only geostationary satellite put up in space exclusively for amateur radio operators. Q stands for Qatar as the satellite was placed in orbit by a Qatar satellite company and 'O' stands for OSCAR (Orbiting Satellite Carrying Amateur Radio).
The challenge was to make QO-100 work for North America.
Transatlantic triumph
On May 11, after two days of trial and testing, Gopan posted on X: "It's done! Thanks everyone for your patience..."
Seated outside the footprint of QO-100, Gopan established computer contact with David (call sign – GOMRF), a ham living right across the Atlantic Ocean in southwest London, a place within the satellite's footprint. "I was constantly in touch with David before I flew down here as he is an expert in this field. So it was him I first contacted," Gopan said from St John's.
The contact was through a computer, using a digital communication mode called FT-8. After David, Gopan contacted 150-plus stations around the world, including in India. For instance Manoj (call sign -- VU2CPL) from Bangalore and Gopan (VU2XTO) from Kochi. And for good measure, he contacted 70 other stations using Morse Code.
Next day, May 12, AMSAT-UK posted on X: "On Saturday, May 11, 2024, Gopan VO1/M0XUU succeeded in making the first contact from North America through the #AmateurRadio QO-100 geostationary satellite transponder located at 26° East." (M0XUU is Gopan's UK call sign. VO1 is the prefix allocated to him for working in Canada. His Indian call sign is VU3HPF)
Gopan chose St John's as it was the North American landmass closest to the farthest edge of the QO-100 horizon. "It was the place where the possibility of success was the highest," Gopan said. In ham language, St John's is minus 0.9 degrees below horizon.
A satellite's horizon, like the one seen from the shore, is the edge of QO-100's footprint or coverage area. Since Earth has a curvature, anything outside the 'horizon' will seem below it. "Now that we know that contact can be established from outside the satellite's footprint, those coming after me can try to connect through the satellite from places that are minus two or three or five degrees below horizon," Gopan said.
Takeaways from the challenge
Gopan's success has offered two insights. One, if there is no obstruction and there is a clear view above the sea, radio signals can travel beyond the fixed boundaries of the satellite. "A satellite's footprint is not really a closed border or a strict cut-off as was originally thought," Gopan said.
Two, about the nature of propagation of super high-frequency waves. Signals from the satellite propagate at a frequency of 10 gigahertz (GHz) and the signals to the satellite operate at 2.4 GHz. "We have not fully understood how it works outside the footprint. But one thing is clear, some ducting is taking place above the ocean or else the signals would have been cut at the edge of the horizon and failed to reach us," Gopan said. In simple terms, ducting is a process by which radio signals are protectively guided or carefully ushered through an atmospheric duct or tunnel.
"There are many islands far outside the footprint where conditions look propitious. I hope others would give these places a try," Gopan said.
Marconi boon
Gopan came to St John’s looking for a spot that offered him the best chance of success. But in doing so he came overwhelmingly close to the spiritual abode of radio enthusiasts: Signal Hill. The hill is just 12 km east of the place from where he won the North American challenge.
On this hill, one-and-a-quarter century ago, Guglielmo Marconi, the Italian physicist who invented the radio, received the first transatlantic wireless signal from Poldhu Point, some 3500km across the Atlantic in South Cornwall, England.
