Radio has played a huge role in human history and is all but unescapable in modern life. Even if you don’t listen to the radio—which is understandable, since what’s being played on it is almost uniformly terrible—chances are good you’ve got at least one radio-ready device somewhere. (Like in your car, for example.) Radio is one of those inventions that now seems like it’s always been around, as if it were just a part of the world since the dawn of time. However, this world-changing device had a long and ramshackle history before a single word was broadcast.
“Wireless Telegraphy” & Electromagnetism
Experiments with wireless communication first began in the 1830s. Researchers started with “wireless telegraphy,” or the transmission of electric telegraphy (telegraph) signals without the use of wires. These scientific trials used inductive and capacitive induction and transmission to send signals through the ground, water, and along train tracks. Though it did work, it was soon discovered that this form of communication was limited in its range, and could not transmit signals far enough to be of any practical use.
By the mid-1870s, Scottish scientist James Clerk Maxwell had proven mathematically that electromagnetic waves could propagate through free space, making good on the theory he put forth in his A Treatise on Electricity and Magnetism. His theory united a number of previously unrelated observations, equations, and experiments on electricity and magnetism (as well as optics) into a single, consistent theory.
Maxwell’s equations—now known as “Maxwell’s Equations”—proved that electricity, magnetism, and light are all part of the electromagnetic field. These equations remain the basis of all radio design, though Maxwell himself had no involvement in further radio research or invention.
Hughes & Hertz
As far as historians can tell, the first intentional transmission of a signal via electromagnetic waves was part of an experiment by Anglo-American inventor and professor David Edward Hughes, circa 1880. Through a series of trial-and-error experiments a year earlier, Hughes had developed a portable telephone device that could pick up “aerial waves” as much as 500 yards from their source.
Hughes demonstrated his technology to representatives of London’s Royal Society, including Sir George Gabriel Stokes, the famed mathematician, physicist, and Cambridge professor. Stokes posited that Hughes’ device operated on electromagnetic induction rather than conduction through the air. Having no background in physics himself, Hughes apparently accepted Stokes’ observation as truth and did not pursue further experiments.
Working off of Maxwell’s theory in the late 1880s, German physicist Heinrich Hertz conducted a series of experiments that proved it. Hertz developed a method by which radio waves (known as “Hertzian waves” at the time) could be intentionally transmitted through free space by a spark-gap device—basically an antenna—and detected over short distances.
By altering the inductance and capacitance of his transmitting and receiving antennae, Hertz was able to gain a modicum of control over the frequencies of radiated waves. Using a corner reflector and parabolic reflector, he was able to focus electromagnetic waves, thus demonstrating that radio waves behaved in the same manner as light waves, just as Maxwell has postulated some 20 years prior.
Despite his successes, Hertz never developed a practical way to utilize electromagnetic waves. In fact, he saw no value in such technology. “It’s of no use whatsoever,” he told students at the University of Bonn. “This is just an experiment that proves Maestro Maxwell was right.” Hertz died in 1894, not long before radio became practical and commercially viable.
Stuck A Feather in His Hat & Called It Marconi
That same year, Italian inventor Guglielmo Marconi set out to build a commercial wireless telegraphy system utilizing Hertzian waves. Building off of the work of Hughes, Hertz, and others, Marconi developed new devices such as portable transmitters and receivers that could broadcast signals over long distances.
By late 1895, Marconi was able to send and receive signals up to two miles, even over hilly terrain. His experimental devices would eventually become the first commercially successful radio transmission system. Marconi’s system has been credited with making possible the rescue of the 700 survivors of the Titanic.
Marconi was granted a British patent in 1896, the first ever for a radio wave system. A year later, he established the world’s first radio station on the Isle of Wight, and the year after that he opened a factory that produced radio apparatuses for commercial sale. He would become the most successful inventor in his field, thanks to the commercialization of his devices. Marconi would win the Nobel Prize in Physics in 1909.