"Wavescan" is a weekly program for long distance radio hobbyists produced by Dr. Adrian M. Peterson, Coordinator of International Relations for Adventist World Radio. AWR carries the program over many of its stations (including shortwave). Adrian Peterson is a highly regarded DXer and radio historian, and often includes features on radio history in his program. We are reproducing those features below, with Dr. Peterson's permission and assistance.
Wavescan, February 13, 2011
Wireless and Radio on Land and at Sea in Antarctica: Tragic News Bulletins from the Antarctic Mainland
Antarctica is a barren and forbidding land, and yet it displays its own unique blend of form and beauty. It is the 5th largest continent and it is located right at the bottom of our planet. The twin names Arctica and Antarctica come from the ancient Greek language and have reference to the northernmost lands and the southernmost lands upon Earth.
The Antarctic continent is more than 3,000 miles across and it is larger than Europe and larger than Australia. Most of the continent is covered with ice and snow one mile deep and it contains more fresh water than is found in the rest of the world. In the harshness of the sunless winter, the temperatures reach more than 100 degrees below freezing, and in the 24 hour sunshine of the summer, the temperatures never reach above freezing. In fact the world's coldest temperature ever recorded was measured at the Russian base Vostok in August 1960 at -127 degrees Fahrenheit, -88 degrees Centigrade.
Although Europeans in their explorations long looked for a continent down under, Terra Australis, yet it was not until the years 1773 and 1774 that the southernmost continent was circumnavigated by the famous explorer, Captain James Cook. This voyage established the fact that Antarctica did exist, but it was not possible for his ships to penetrate through the ice floes and make a landing in the coastal areas. The first humans to land on the Antarctic continent were crew members from a seal hunting expedition led by the American, Captain John Davis on February 7, 1821.
These days 30 different countries operate permanent research stations on the Antarctic mainland, and an additional 30 temporary camps are established each summer. The winter population in Antarctica is around 1,000, and the summer population is around 4,000, all of whom are involved in various forms of scientific research.
It was on December 2, 1911, that the small ship Aurora left Hobart Tasmania with personnel and equipment for exploration into the Antarctic regions. The expedition was led by Dr. Douglas Mawson and the first point of call nine days later was Macquarie Island where a small party of men disembarked for the purpose of establishing a wireless station to act as a relay station between Australia and the Antarctic mainland.
A month later, the ship Aurora arrived further south in Commonwealth Bay, Antarctica and they established a base camp at Cape Dennison. Work commenced on the installation of a wireless station, the very first on the Antarctica mainland, but the work was very slow, due to the harshness of the environment.
The equipment for the wireless station consisted of a 1-1/2 kW Telefunken spark transmitter tuned to 500 KHz, a French made 9 horsepower Dedion petrol engine as the electricity generator, a sloping aerial system with masts 115 ft. high and 20 ft. high, and a simple crystal set receiver. Transmissions from this station began in September 1912, though it took a long time before meaningful messages got through.
We list now, several of the messages that were transmitted from the Antarctic mainland, taken from contemporary documents and newspaper reports, though we have been unable to discover just what callsign was in use at this wireless station.
During the time of its active operation, the Antarctica wireless station was occasionally heard by station MQI on Macquarie Island, which lies about half way between Australia and Antarctica, and on these occasions news was also passed on for publication in Australia and the United States. There were occasions when Antarctica was heard in New Zealand; and just once only was Antarctica heard in Hobart Tasmania, and by AWA Pennant Hills in Sydney.
The Antarctica station complained about interference from other wireless stations in Australia, from ships plying the waters south of Australia, and by spark discharges from the antenna system, known as St. Elmo's fire.
With the increase in daylight, communication by wireless was no longer possible and the station was closed. Thus, the first wireless station on the Antarctic mainland was on the air from September 1912 to November 1913. It was in use for a little over a year, in the transmission of personal messages, official communications, and news reports for publication.
Radio Panorama RP8: Signaling through the Earth
In the early eras of history, electricity was observed as a static phenomenon; that is, an electrical charge was observed for example, when amber material was rubbed with a cloth. The electrical charge remained on the surface of the amber for a period of time, and it did not dissipate immediately; that is, it was not a form of flowing electricity, but it was a stationary, or static charge.
However, when experimenters began to generate and experiment with moving, or current electricity, they discovered that a circuit was involved. In other words, it was not possible to induce a moving current of electricity through a single open wire, there had to be a return for the electricity, a circle, a circuit.
It would be suggested that the need of a closed circuit for the flow of electricity was first demonstrated at the time when Luigi Galvani in Italy joined two wires, zinc and copper, and touched the other end of each wire on the leg of a frog. This procedure made the muscles of the frog twitch. Although it was not understood clearly at the time, back in the year 1780, this experiment demonstrated the flow of electricity through a closed circuit.
Likewise, 20 years later, Alessandro Volta also in Italy, invented, developed, the battery cell. He inserted two joined wires, zinc and copper into a solution of salt water and he discovered that this created a flow of electricity, an electrical current.
During the year 1837, both Samuel Morse in the United States and Cooke and Wheatstone in England developed a telegraph system with the use of a twin wire circuit. That is, the electrical signal had to travel from the first location along a connecting wire to a second location, and back to the original location along another wire.
However, during the following year, 1838, Professor Karl von Steinheil in Munich Germany experimented with the concept of using the earth as the return segment of a telegraph circuit, thus eliminating the need for the return wire. He inserted a metal plate into the earth at each end of the telegraph circuit. He suggested that therefore it might be possible to use the earth itself as a connecting medium for the transmission of a telegraph signal, a wireless signal if you please.
When the Overland Telegraph was constructed in Australia in 1872, a single galvanized iron wire connected Darwin in the north and Adelaide in the south, a distance of nearly 2,000 miles. Each end of the wire was enabled with an earth connection.
In 1866, the dentist Mahlon Loomis, experimented with the concept of using the sky and the earth as the twin connecting media for a wireless telegraph circuit. He flew two kites, each with a spark gap and a connecting wire onto a plate in the ground, at a distance of 14 miles in the Blue Ridge Mountains in the American state of Virginia. This system worked, but he did not realize that he had succeeded in transmitting a wireless signal through the sky, not through the ground.
In 1880, Professor John Trowbridge at Harvard University in Cambridge, Massachusetts experimented with the concept of transmitting wireless signals through the earth and he successfully received the university's ticking time signals at a distance of one mile. However, he discovered that the signal strength quickly dissipated due to the fact that the signal transmitted through the earth was omnidirectional at ever widening circles.
Now when Guglielmo Marconi began his early wireless experiments in Bologna, Italy, he discovered that he could transmit a wireless signal over a significant distance with the use of a spark gap transmitter and a spark gap receiver, each connected to an elevated aerial and an earth plate inserted into the ground.
Almost simultaneously, Alexander Popov in Russia developed a workable wireless system using a similar concept.
Thus it was that early wireless experimenters discovered that the earth could be used as a transmitting medium for wireless signals though it was a highly inefficient procedure. However, when wireless and then radio came to stay, the usage of an earth grounding did play an important part in the circuitry.
Another concept for the early wireless experimenter was the usage of water as a connecting medium for the transmission of intelligible signals, and that's our story for another occasion.