Although radio is sandwiched between two revolutionary communication technologies — the telegraph and the television — the medium has remained remarkably resilient. First broadcast at the end of the 19th century, radio continues to provide the soundtrack to countless commutes. However, its importance goes far beyond local shock jocks and Top 40, and it still underpins the modern world. Here are six amazing facts about radio, from its remarkable discovery to its transformation into a world-changing communication system.
Radio Waves Were Theorized Before They Were Discovered
The scientific community knew about radio waves before anyone discovered actual evidence of them. In 1865, Scottish mathematician and physicist John Clerk Maxwell predicted the existence of radio waves in a paper titled “A Dynamical Theory of the Electromagnetic Field,” based on a presentation he gave before the Royal Society in December 1864. He also developed a set of electromagnetism equations known to history as “Maxwell’s equations.”
Although Maxwell gave due deference to his predecessor Michael Faraday, who had discovered electromagnetic induction among other principles of electromagnetism, many consider Maxwell’s work — which predicted various waves along the electromagnetic spectrum — a pivotal moment in the history of science and technology. These waves remained theoretical for more than 20 years, until German physicist Heinrich Hertz demonstrated radio waves for the first time in his laboratory in 1888 — forever transforming the history of communication.
The First Reported Transatlantic Radio Transmission Might Never Have Happened
Although Hertz got his own unit of frequency for his trouble, the undisputed giant of early radio is Italian inventor Guglielmo Marconi. After studying the work of Maxwell, Hertz, and other influential physicists while growing up, Marconi sent a radio signal more than a mile at his estate in Pontecchio, Italy, in 1895. Sensing both opportunity and celebrity, Marconi took out several patents and demonstrated his system throughout Europe. Then, on December 12, 1901, Marconi set out to prove that radio waves were not impacted by the curvature of the Earth. With a transmitter set up in Newfoundland, Canada, and another in Cornwall, England, some 2,100 miles away, Marconi waited for the three clicks (the letter “S” in Morse code) coming from Cornwall to prove that his invention — and the radio waves it produced — could work across long distances. Accompanied by his assistant George Kemp, Marconi believed he heard the expected three clicks, proving that his invention worked. Kemp also agreed that he heard the clicks.
Today, many experts are skeptical that the pair actually heard the clicks, since Marconi had many motives to act as if they did (and Kemp may have gone along). There were no independent witnesses, and it’s highly implausible the technology would have been capable of producing a transatlantic transmission at the time. It’s likely we’ll never know for sure what really happened that day.
The Most Powerful Radio Station Ever Was in Cincinnati, Ohio
In May 1934, President Franklin D. Roosevelt pushed a button in the White House, and the world’s first “super station,” WLW, came to life near Cincinnati, Ohio. The station used an 831-foot, 500-kilowatt tower capable of sending a signal halfway around the world. The project was designed as a temporary experiment to spread radio waves far and wide, but unfortunately, its immense power and operating costs proved to be too much. Stations far away from Cincinnati but still within range of the 700-hertz frequency complained of constant interference. People living close to the tower also reported hearing the broadcast vibrating along metal kitchen pans, barbed-wire fencing, or even bedsprings. After five years, Congress decided 500 kilowatts was simply too powerful, and limited broadcasts to 50 kilowatts — the current limit for AM clear-channel stations today.
The First Radio Commercial Was for a Real Estate Developer in NYC
In August 1922, New York radio station WEAF created something that would change the radio industry forever — it broadcast the very first radio commercial. The ad spot was for an apartment complex in Jackson Heights, Queens. Although radio ads are an obvious innovation now, one worry among early radio stations was how to make money from the service, since people weren’t charged for the endless stream of programming itself. Initially ads may not have seemed like a profitable strategy given the limited number of listeners, but economics changed as more radios began to find their way into American homes. Between 1923 and 1930, the number of Americans who owned at least one radio jumped to 60%, meaning that there were enough listeners for the radio ad business to be booming.
Radio Is an Extremely Important Tool for Astronomers
Because radio waves are part of the electromagnetic spectrum — one of the fundamental forces of nature — stars, quasars, planets, galaxies, and dust galaxies emit them. Some of the earliest attempts to use radio to investigate the stars came at the turn of the 20th century, when astronomers attempted to pick up radio emissions emanating from our sun. Today, radio astronomy is an entire field of dedicated scientists pointing massive radar arrays at the stars in an effort to glimpse things unseen by the naked eye. One of the most impressive radio telescopes in the U.S. is the National Radio Astronomy Observatory’s Robert C. Byrd Green Bank Telescope located in West Virginia. The telescope is the largest fully steerable radio telescope in the world, and the machine is so sensitive to radio waves that Wi-Fi is illegal in the 13,000-square-mile “National Radio Quiet Zone” surrounding the telescope.
The Eiffel Tower Avoided Destruction Because of Radio
It’s hard to imagine Paris without the Eiffel Tower, but the iconic tower wasn’t meant to stick around forever. Gustave Eiffel originally built his eponymous tower for the Exposition Universelle of 1889, and the city only leased the land to Eiffel for 20 years. After that, the land was to be returned to Paris and the tower demolished. Knowing the destruction in store for his precious monument, Eiffel set about finding some way to make the tower both useful and symbolic. On November 5, 1898, the Eiffel Tower participated in an early demonstration of radio when a signal was sent from the tower’s tip to the Pantheon some 2.5 miles away.
In the early 20th century, Eiffel doubled down on transforming his monument to progress into a full-fledged radio tower. By 1908, radio waves emanating from the Eiffel Tower could reach distances of more than 3,500 miles, and its creator had successfully proved its strategic worth. The Eiffel Tower then proved vital during World War I as it intercepted radio messages sent by the Central Powers. Today, the tip of the Eiffel Tower is still home to various radio antennas.