Grimeton Radio Station

Grimeton Radio Station was in 2004 inscribed on the UNESCO World Heritage List. The Swedish-American Ernst Alexanderson had developed a technology for wireless telegraphy which came to be used at the radio station in Grimeton. Today, the long-wave transmitter at Grimeton Radio Station, with its alternator and multiple antenna, is unique as the only surviving radio station from the time before radio tubes for high power.

The station in Grimeton, with the callsign SAQ, first started to operate in 1924, mainly for telegraphy with America. The experiences of broken cable connections during the First World War, lead to the decision in the Swedish Parliament in 1921 to build a radio station in Sweden to send morse telegrams across the Atlantic. The premise was to be independent of other countries cable networks.

In the 1920’s, the industrial race, peace efforts and emigration spurred technological development onward.

Bids were requested from Telefunken in Berlin, The Marconi Company in London, Radio Corporation of America (RCA) in New York and Société Francaise Radio-Electrique in Paris. RCA with its high frequency alternator constructed by the Swedish-American Ernst Alexanderson was chosen. After careful calculations, the Swedish station was placed in Grimeton, from where the radio waves were given free passage to the west sea, and over the Atlantic.

During the Second World War 1939-1945, the radio station in Grimeton experienced a heyday, when it was Scandinavia’s gateway to the outside world. Cable connections had once again been quickly destroyed by nations at war and the wireless telegraph was a link to the world.

Grimeton Radio Station is now the only station left in the once transatlantic network of nine long wave stations that were built during the years 1918-1924, all equipped with the technology that was constructed by Ernst Alexanderson. Alexanderson’s long-wave technology from the 1920’s is still fully operational, and is used on special occasions every year.


Ernst Fredrik Werner Alexanderson was born in Uppsala, Sweden, on January 25, 1878. After studies in Lund, Stockholm (where he received a Master of Engineering) and Berlin he came to the USA in 1901 and soon began working at General Electric in Schenectady, Massachusetts.

This was the time when the first successful experiments to distribute electrical currents over long distances were approximately ten years old. Yet, even in this short time span, electricity as a power source had been widely introduced. Apart from illumination, electric power came to replace earlier sources in mines, the iron industry, saw mills and the pulp industry. Within communications and the chemical industry electric power gained new areas of application.

Some years before the turn of the century, Marconi succeeded in transmitting Morse signals over longer and longer distances. Wireless telegraphy was born and became another example of the conquests of electricity.

Alexanderson came to the USA at a time when electrical power totally dominated development within electrical technology. No one at that time anticipated the explosive developments to come, first in wireless telegraphy and later in voice broadcasting with John Ambrose Fleming’s invention of the first electron tube, the diode. No one could anticipate the origin of what today is called electronics, which now extends to all areas of technology.

Alexanderson died in the year 1975, and in his lifetime had, except during his sickness in his final years, not only experienced but also in various ways contributed to development in all the various areas of electricity. He thus worked with the design of generators and motors, transfer of high tension dc power, control technology, telegraphy and telephony, radio and television and computers. During both the First and Second World Wars he contributed with innovations in the military area, such as electric propulsion of boats, aids for airport landing in fog and pulse-echo equipment for identification of grenade fire.
During the period 1905-1964, with exceptions for the years 1945, 1954 and 1960, he was granted new patents each year. The final patent was granted in the year 1973. In total he received 344 patents.

During the period 1905-1964, with the exception of the years 1945, 1954 and 1960, he was granted new patents each year. The final patent was granted in 1973. In total he received 344 patents, the last at age 95. For his work with the alternator (the technology which in the long-wave transmitter Grimeton is built upon) Alexanderson in 1983 posthumously was included in The National Inventors Hall of Fame, an honor he shares with Bell, Edison and Marconi.

Alexanderson was a very well-known person in the United States, far more than in Sweden, where he is remembered for his installations in Grimeton. His legacy has been well managed and when you hear and see the 50-tonnes long-wave transmitter rumbling during the start-up and the relays chattering, we remember Ernst Alexanderson, as “The Complete chief engineer”.