At the turn of the twentieth century, researchers across Europe and North America were competing to create wireless communication systems for commercial and military use. Telefunken emerged as the second-largest wireless company in Europe after the British Marconi Company. It was created by two giant German electrical power companies, Siemens and AEG in 1903 as the “Telefunken Society of Wireless Telegraphy” under the direction of AEG’s Adolph Slaby and George von Acro. Thanks to the research of former Siemens scientist Karl Braun, who shared a Nobel Prize in Physics with Guglielmo Marconi, Telefunken would quickly become a world leader in wireless technology. Through the rest of the century, it pioneered the development of radio, electronics, radar systems, and television.

Telefunken developed an extensive wireless transmission system in the early twentieth century based on long-range communications. In 1911, it finished work on a 200 meter tall antenna mast that broadcast at 500 kilowatts—enough power to reach the German colony in Togo, Africa. Although this antenna collapsed in a storm, Telefunken remained a key asset for the German military. It created wireless systems for the German navy and army, including a station that could reach German submarines.

In addition to developing German military infrastructure, in 1911, Telefunken built a continuous-wave type transmission system across the Atlantic Ocean by building three 180-foot towers in Sayville, New York. When the war broke out, the Sayville station came under fire from the American public. Some suspected that the Germans were using their American installation to send coded signals to aid them in their undersea campaign, including the sinking of the Lusitania in 1915, and may have been used to transmit the infamous Zimmerman telegraph plotting a German-aided Mexican attack against the United States in the event of war. The Americans seized Sayville during the war and retained it afterwards as reparations.

Telefunken set up the first vacuum-tube based broadcasting transmitter in Berlin in 1923. As demand for radio spread, its parent companies Siemens and AEG built their first receivers with the Telefunken trademark. For the next forty years, Telefunken radio receivers and tubes became renowned across Europe for their quality.

Telefunken again became vital to German military power in the Second World War, when it developed early-warning radar systems for German air defenses. Beginning with long-range radar systems based on vacuum tubes, its researchers developed Klystron radar generators by 1942. Initially, these short-wave systems could accurately target Allied bombers, allowing anti-aircraft guns and fighter planes to attack them with deadly accuracy. But the Allies soon found a simple way to deflect this radar using thousands of tiny aluminum strips to blind the signals.

After the war, Telefunken was an innovator in the fields of television, audio, and consumer electronics. In 1950, its Hanover factory began building high-fidelty stereo equipment and vacuum tubes considered among the world’s best. In 1963, it developed the PAL analog color television standard, which also proved to be a global leader. But by the late 1960s, strong competition from Japanese manufacturers essentially put the company’s consumer electronics arm out of business. Telefunken merged with AEG. After a subsequent set of corporate acquistions and maneuvers, Telefunken’s legacy lives on in new products, such as microphones, which bear its logo but are manufactured outside of Germany.