The beginning of radio
Radio would never have developed if scientists had not discovered electromagnetic waves during the 18th century. They then went on to develop the wireless telegraph. The first of what came to be considered the first transmission of radio waves was achieved by the Italian Guglielmo Marconi in the late 1800s, with the signal successfully transmitted as far as 2 miles. He then later established a radio station on the Isle of Wight in England. Marconi is credited for the invention of radio and was even awarded a Nobel Prize for Physics.
By the 20th century radio had spread around the world and the radio program which broadcast the news began in Detroit in 1920. College radio stations came about at roughly the same time, with early stations starting to appear in New York State. Radio also became important in marine circles in the early 1900s for communication among and between ships and land. In terms of safety, it became very important to have a reliable radio system that was manned 24 hours a day by someone on the ship.
It was in 1906 that Lee de Forest and Reginald Fessenden developed the amplitude-modulated or AM radio. The significance of this invention was that now more than one radio station was able to transmit signals, which was a major advancement in radio history.
From crystal sets to vacuum tubes
The first radios that were created used crystal sets. In the 1920s this changed, and we see the development and use of vacuum tubes in radios. This really helped in the progress and advancement of radio transmitters and receivers.
The invention and development of frequency-modulated (FM) radio came about in 1933 and was invented by Edwin H. Armstrong. The advantages of FM over AM were that the sound quality was greater because of the higher bandwidth that was used. As a result, many radio stations switched to using FM over AM.
Radio in Education and Entertainment
People soon recognized that radio would be a good medium for transmitting educational information to the general population. Therefore, educational programs soon started to be broadcast over radio. Various experts could use radio to discuss topics and help to educate large numbers of people.
When most think of radio, they think more about how radio is used for entertainment purposes, and certainly there is a lot of music that is played on the air today. There are also programs which range from political discussions to comedies.
Internet and Satellite radio
The most recent advances in radio since the mid-1990s and into the 2000s has been in internet and satellite radio. People can listen to music on the computer and most radio stations have a website today that stream the music. Satellite radio has been the most recent development we have seen withing the technology. Many people subscribe to this form of radio because it is commercial free, and they get a wider range of programs and songs to listen to.