Alexanderderson Day - humble great inventor

Source: www.sciencephoto.com

Few people know about Ernst Alexanderson. The name of this very talented engineer is lost in the radiance of the names of his brilliant colleagues - Thomas Edison, Guillermo Marconi, Nikola Tesla, Alexander Popov ... However, Aleksandrson has 345 patents for inventions related to electrical engineering and radio electronics, and he is rightfully considered one of the pioneers of broadcasting and television; He received his last patent when he was 89 years old! Unlike the famous inventors, whose names are on everyone’s lips, Aleksandrson did not strive for fame, did not participate in high-profile scandals and stories, but simply worked, inventing and creating devices that are very necessary and important for nascent electronics.




Ernst Frederick Warner Aleksandrson was born in Sweden in 1878. In 1902 he emigrated to America, where he began working at General Electric. In 1904, at the age of 26, he created, probably, the most spectacular radio machine in the history, which was intended for serious work, and not for the fun of the most respected public (a pebble was thrown into the front yard of Nikola “our whole Tesla”) ... This car - mechanical generator of radio frequency oscillations - received the name "alternator".


Source: www.tekniskamuseet.se

The Alexanderderson alternator could generate a signal with a frequency of up to 100 kilohertz. It is clear that it is impossible to spin the rotor of the machine to such a speed. The alternator shaft rotated at a speed of the order of several thousand revolutions per minute, but due to the special configuration of the coils at the generator output, the desired high frequency was obtained. The design of the alternator turned out to be very successful. They were used on radio stations until the 60s of the last century, that is, even when tube generators had already appeared and were used in full. The disadvantages of these machines were the large size and weight, and because of this they could not be installed on ships.
It was the Aleksandrson alternator that allowed the world's first voice broadcast on December 24, 1906 from the Atlantic coast of the United States. Actually, it was for this purpose that it was created: without a generator of undamped radio-frequency oscillations, it is impossible to transmit voice over the radio.


Source: wikipedia.org

Technological progress is relentless. With the advent of more advanced generators, alternators went to landfill (or perhaps remelting). And today in the world there is only one working alternator. It is installed in the building of the Grimeton radio station, which is located near the Swedish city of Varberg. This radio station can be called memorial: it was founded by Ernst Alexanderson in 1922, being at that time the chief engineer of the Radio Corporation of America (RCA). In his honor, all the equipment of the radio station is maintained in working condition.


Source: alexander.n.se


Source: flickr.com

July 2 is considered the day of Alexanderson. Every year, on Sunday closest to this date, the alternator is launched, and, like many years ago, at the frequency of 17.2 kilohertz the Morse code callsign SAQ radio stations and congratulations on the air are transmitted. What could be a better recognition of the merits of an engineer than the equipment he created and is still working?




Source: alexander.n.se

This year, the Grimeton radio station will air on June 29. The transmitter will be turned on at 8:30 UTC, and transmission will begin at 9:00 UTC. The ceremony will be repeated at 11:30 UTC.
Unfortunately, without proper preparation it is impossible to listen to the broadcast live. We need a super-long-wave antenna and a receiver, and there is no guarantee that something will be caught at decent distances from a radio station, for example, in Moscow. But the very opportunity to hear the voice of equipment that has already forever gone makes this day probably the most moving technical holiday.
Ernest Alexanderson died in 1975. For his services, he was awarded the Medal of Honor and Edison of the Institute of Radio Engineers (now IEEE), and after his death, the name of Alexanderson was included in the books of the National Inventor Hall of Fame (NIHF) and the Consumer Electronics Association Hall of Fame (CEA). Grimeton radio station was included in the UNESCO World Heritage List.


Source: ieeexplore.ieee.org

In conclusion, two videos: the Aleksandrson alternator at work and the reception of a signal from the Grimeton radio station.