The old-time radio era, sometimes referred to as the Golden Age of Radio, was an era of radio programming in the United States during which radio was the dominant electronic home entertainment medium.  It began with the birth of commercial radio broadcasting in the early 1920s and lasted through the 1940s, when television gradually superseded radio as the medium of choice for scripted programming, variety and dramatic shows.

1920's

Most radio historians asert that radio broadcasting began in 1920 with the historic broadcast of KDKA.  Few people actually heard the voices and music which were produced because of the dearth of radio receivers at that time.  The public, however, was overcome by a radio craze after the initial broadcast.  Radio became a product of the mass market.  Manufacturers were overwhelmed by the demand for receivers, as customers stood in line to complete order forms for radios after dealers had sold out.  Between 1923 and 1930, 60 percent of American families purchased radios.  Families gathered around their radios for night-time entertainment.  As radio ownership increased, so did the number of radio stations.  In 1920, KDKA was not actually the only operating radio station, but it remains a benchmark in most accounts. And by 1922, 600 radio stations had sprung up around the United States. 

1930's

For the radio, the 1930s was a golden age. At the start of the decade 12 million American households owned a radio, and by 1939 this total had exploded to more than 28 million.

As technology improved radios became smaller and cheaper. They became the central piece of furniture in the average family’s living room, with parents and children alike, crowding around the set to hear the latest instalment of their favourite show.
Radio may have had such mass appeal because it was an excellent way of uniting communities of people, if only virtually.
It provided a great source of entertainment with much loved comedians such as Jack Benny and Fred Allen making their names on the wireless.
It marked the advent of the soap opera, a running story that people could return to, with characters they could sympathise with and love. The series ‘Our Gal Sunday’ - about a small town girl finding love with a wealthy Englishman - had the young women of the country glued to their sets.
Radio programs provided a source of inspiration, with heroes like the Lone Ranger and The Shadow getting embroiled in deadly capers. But they also promoted old-fashioned American family values and gave people a model to live by. On Wednesday nights at 8pm when the public tuned in to ‘One Man’s Family’ they were greeted with the opening: ‘Dedicated to the mothers and fathers of the younger generation and to their bewildering offspring.’

1940's

During American radio’s Golden Age, much of the programming heard by listeners was controlled by advertising agencies, which conceived the shows, hired the talent and staff (sometimes drawing performers directly from the old vaudeville theatre circuit), and leased airtime and studio facilities from the radio networks. Programs became fixed in quarter-hour and half-hour blocks and featured a wide variety of formats. Soap operas such as Ma Perkinsand The Guiding Light kept housewives company through the afternoon. Children listened to the adventure series Little Orphan Annie and the science-fiction show Flash Gordon.  Amos'n' Andy, a situation comedy, was the most popular show ever broadcast, lasting more than 30 years. The Shadow, a crime drama, also had a loyal following. “Prestige” anthology shows brought together writers such as  Archibald MacLeish and Norman Corwin with actors from the legitimate stage such as Helen Hayes and Orson Wells.