Explore the changing methods people used to listen to radio in its early days, from wireless telegraphy to transistor radios.

Early users of radio could only receive and transmit the electromagnetic pulses used in Morse Code. Although Marconi developed the first wireless system in 1895, the first voice broadcast of radio did not occur until 1906.

By the early 1920s, most radios detected sound using tiny galena mineral crystals. Headphones, modified from a telephone receiver, could be used to listen to the sound.

In 1922 GE created a series of images of a young girl demonstrating the different methods of listening to radio. Here she listens to a Radiola V radio receiver using headphones.

Engineers developed loudspeaker horns so that more than person could listen to a radio receiver at a time. The horns used a variation of an early headphone speaker as the sound source, and used the horn to amplify the sound.

The Radiola III was the first mass produced radio, with 293,000 receivers manufactured. There were fewer than 10,000 manufactured of its predecessor, the Radiola II. It cost $35 to purchase at a time when a radio engineer earned a starting salary of $27 per week. This radio was owned by GE radio inventor Ernst Alexanderson (1878-1975).

The young girl listens to the Radiola V using a loudspeaker horn. The horn had a limited sound quality and no ability to increase the volume, so engineers sought a better way to produce sound from a radio.

This was a prototype of the loudspeaker developed by Clarence Hewlett, Edward Kellogg and Chester Rice at the GE Research Laboratory for use in radios and theaters.

The Radiola 28 radio receiver (left), cost $260 but did not include a speaker. In advertising it was often paired with one of the electrodynamic loudspeakers, the Radiola 104. The original cost of the Radiola 104 was $260, at a time when an entry level radio engineer earned $27 per week.

A young girl listens to an RCA Radiola IV radio through a built-in speaker

The Radiola 26 was one of the first truly portable radios, despite weighing 25 pounds. In addition to being one of the first radios with a built-in speaker, the antenna is part of the door, and the radio also contains a battery compartment in the rear. The radio sold for $225.

The development of the transistor radio, replacing vacuum tubes, allowed engineers and designers to shrink the size of the radio. Because transistor radios were pocket-sized and portable, headphones came back into popularity, including a new variation, the earbud.

Standards for Listening to Radio