by Barry Mishkind

TUCSON, Arizona - Perhaps it shouldn't surprise us, but the majority of broadcast station staffers have never seen a transmitter. In fact, few ever even stop to consider the mechanics of how their voice gets from the microphone to the listener's radio receivers.

Perhaps this matters more to the technical folks than the rest, but the story of the invention of transmitters capable of sending music and voice is fascinating and involves a key pioneer who is nevertheless relatively unknown today: Dr. Ernst Alexanderson.

The very early wireless pioneers like Hertz and Marconi developed spark transmitters which opened up the airwaves to telegraphic communication. Soon, Morse code filled the air, crossed the ocean, and brought the world much closer. News could be transmitted instantly, but only using the inefficient "crashes" of the spark machines.

The real breakthrough that led to the vibrant industry of broadcasting was the ability to send voice and music to receivers. The man who developed the high frequency generator that made this possible, and much more, was Dr. Ernst Alexanderson.

Ernst Alexanderson

Alexanderson was born in Upsala, Sweden in January 1878, son of a judge and professor of Greek. Developing an early interest in electrical engineering, he attended the Royal Institute of Technology in Stockholm, and did post- graduate work at the Technical University in Berlin, Germany.


It was in Berlin that Alexanderson read Alternating Current Phenomena. The book, by Dr. Charles Steinmetz the mathematics genius at General Electric, inspired him so much he decided he had to come to the US to meet Steinmetz and seek work with him at GE. This he did in 1902. Thus began a career of invention that brought Alexanderson a total of 344 patents, third only to Thomas Edison and Elihu Thompson, who would become the founders of General Electric.

Among Alexanderson's first assignments was one initiated by Professor Reginald Fessenden. Fessenden had been seeking to improve on the spark transmitters by building a transmitter which produced a continuous wave carrier upon which he could attach the human voice. Most alternating generators of the time were limited to about 60 Hertz. Fessenden knew he needed a much higher frequency.

However, Fessenden's own experiments failed to create the necessary machine; he was not able even to get as high as 1,000 Hertz. So, in 1904, Fessenden turned to GE, and set a rather impressive goal for Dr. Alexanderson: a machine which would generate a frequency of 100,000 Hertz.

It took two years, but in 1906, Alexanderson had constructed a 2 kW, 100 kHz alternator. Fessenden installed it in his transmitter at Brant Rock, MA, and the historic Christmas Eve broadcast took place. Following a series of "CQ" transmissions in Morse code, radio operators who were monitoring that night were astonished to hear Fessenden's voice reading the Bible and poetry. As wireless rooms filled with the curious, a woman was heard to sing! The program concluded with a violin solo and short speech.

Broadcasting is born!

The Alexanderson Alternator became the basis for all sorts of experiments and broadcasts. Marconi bought a 50 kW, then a 200 kW Alexanderson Alternator for his transatlantic station at New Brunswick, New Jersey. In 1918, this station would be used to transmit President Woodrow Wilson's ultimatum to Germany, bringing the First World War to a close. The station also permitted Wilson to stay in telephonic contact with the US during his trip to the Peace Conference at Versailles, France, and back.

To show how much Marconi understood the importance of the clear audio produced by Alexanderson's alternator, he tried several times to buy exclusive rights to the alternator technology from GE. Interestingly, it was President Wilson himself that appealed to GE not to do so, eventually helping organize a new company with Dr. Alexanderson at the helm to continue the development of his alternator: the Radio Corporation of America (RCA).

During the next five years Alexanderson worked at both GE and RCA. Focusing on the new technology of broadcasting, he developed a set of 12 multiple tuned directional antennas on Long Island, one of them ten miles long. He did the pioneering work on transmission of pictures by radio, television and much more.

George Michael, who interviewed Dr. Alexanderson in 1947 on the NBC radio network, told me "Alexanderson was ready for TV in 1922, but his bosses said, 'Let's get radio off the ground first.'" WGY became the testing ground for much of Alexanderson's work, including the development of higher power transmitters, 50 kW, 100 kW, all the way up to 500,000 watts.

However, Alexanderson couldn't be kept on one project for long. A "mild- mannered, unassuming man", according to Michael, "Alexanderson would set out his theories and move on to something else, letting the GE labs finish off his projects." Interestingly, "it appeared he didn't realize how important he was in terms of the inventions. He saw them merely as just another challenge."

As one challenge after another was surmounted, Alexanderson moved from audio to video. In 1924, he sent a handwritten note from New York to his father in Sweden. Two years later, he sent the first facsimile transmission to go around the world. Passing through successive relays, the picture was reproduced on machine in the same room as the transmitter after just two minutes.

By 1925, Alexanderson was experimenting with television, broadcasting to something over 300 TV sets in Schenectady, NY. By 1928, Alexanderson demonstrated microwave tv transmission, as well as the first broadcast of a professional television drama: The Queen's Messenger, on September 11, 1928.

Alexanderson's experiments reached into all sorts of electical engineering, an audio recording system using film in 1927, a mechanical system for color television displayed in 1930, a telephone system to connect trains, light transmission (in 1927, he developed a "multiplex system" so radio stations could send four channels on light beams), and a secret telegraphy system used by the military. In 1928, Alexanderson discovered the radar altimeter, the forerunner of the radar developed by the British almost 20 years later. He even foresaw a time when electricty could be transmitted through the air.

Michael himself reports when he was newly at WGY, in 1945, he found himself with the opportunity to be the first to field test another of Alexanderson's inventions, the portable sound recorder. Up until that time, recording audio in the field required a large van with disk transcription equipment. Michael was able to carry this new unit out and bring back audio from all sorts of venues.

By and large, Michael reports, "over the years, Alexanderson virtually invented everything GE did in the field of AM, FM, and TV."

Over the years, one honor after another recognized Dr. Alexanderson for his contributions over the years. He was elected to the Royal Academy of Science in Sweden, he received the Medal of Honor from the IRE in 1919, Knighthood in Poland in 1924, The Edison Medal from the American IEE in 1944, the Royal Danish Medal in 1946, etc. etc.

Several of the original Alexanderson Alternators can be found today in the museum set up in Grimeton, Sweden. In 1996, one was turned on during the 80th anniversary celebration. The station worked just it as it did in 1916, and transmitted signals back to the US.

Living to 1975 and the age of 97, Alexanderson watched many changes occur to the electronics and broadcast industries. He felt it was important for engineers use foresight in their experimentation, not merely developing only those inventions that appear to be immediately profitable. He counseled younger engineers to be wide-ranging in their interests and focus, as that led to solutions to engineering problems instead of "specialization [which] cramps imagination".

Alexanderson was certainly one of the key figures in radio and TV history, if not a piviotal one, although he is not often given the recognition today that some, including George Michael, feel he is due. Some would call him Father of Radio and TV. What is clear is that Alexanderson's life work holds a great deal of interest for anyone who wants to understand broadcasting.

Spurred by his contact with Alexanderson, Michael has done a lot of research into the history of this broadcast pioneer, some of which is found at Union College's Schaffer Library in Schnectedy and at the American Wireless Association Museum in Holcomb, NY. My sincere thanks to Michael for sharing his efforts with me.

Barry Mishkind, aka the "Eclectic Engineer," can be found via