© Mark Ollig
National Defense Day was first celebrated Sept. 12, 1924, to commemorate the World War One Battle of St. Mihiel.
Between Sept. 12 and 15, 1918, Major General John J. Pershing led the European American Expeditionary Forces in a successful offensive in the Saint-Mihiel strategic area in northeastern France, controlled by the German army since 1914.
American and French troops worked together to achieve a significant victory, which marked a critical turning point in World War I.
A few years after World War I ended Nov. 11, 1918, the US War Department recognized the need for a reliable national broadcasting network to communicate with citizens immediately in an emergency.
No nationwide radio broadcasting networks existed in the early 1920s; however, radio transmission was still regarded as the most effective means of instantly reaching the most people.
Although there were some licensed stations, it was mainly unlicensed amateur radio stations transmitting low-powered broadcasts to crystal homemade battery-operated radio receivers.
And so, nearly a century ago, a determined technological and engineering test would take place over a radio broadcasting medium.
The US War Department’s National Defense Test, a coast-to-coast broadcast showcasing radio’s potential for use in an emergency, would coincide with National Defense Day Sept. 12, 1924.
The objective was to demonstrate instant communication to a national radio-listening audience.
AT&T proposed a “chain broadcasting” radio network to transmit government radio broadcasts from Washington, DC, through the nation’s long-distance telephone voice network, which AT&T was still constructing, to specific radio stations for them to broadcast over the air.
This method enabled the best means for efficiently distributing audio content from Washington, DC, to individual radio receiver sets.
Telephone engineers played a crucial role in facilitating the efficient transmission of radio signals across the country’s growing wired telephony infrastructure.
The National Defense Test would see 18 radio stations physically linked across the United States transmit audio from the US War Department through amplitude-modulated signals directly to American radio sets nationwide.
On Sept. 4, 1922, WLAG radio station started broadcasting from the sixth floor of the Oak Grove Hotel in Minneapolis.
Financial challenges forced the station’s closure July 31, 1924; however, WLAG received special permission to turn its equipment and transmitter on again to broadcast the National Defense Day Program.
On Sept. 12, 1924, a National Defense Test radio program was broadcast from the US War Department in Washington, DC, to promote National Defense Day.
Audio communication from the US War Department in Washington, DC, was transmitted via long-distance phone line networks to radio stations, relaying the audio signal to individual radio sets nationwide.
The program featured military-related content such as speeches, music performances, and simulated battle scenarios.
The broadcast raised public awareness for national defense, promoted patriotism, and showcased the military’s use of this nation’s technological capabilities.
Cooperation between engineers and technicians from AT&T, RCA, and independent telephone companies led to installing and testing equipment and telephone line facilities to ensure reliable transmission and reception of radio signals between radio stations relaying the broadcast from Washington, DC.
On Sept. 12, 1924, eighteen radio stations participated in the National Defense Test by broadcasting live voice transmissions from the nation’s capital to individual crystal and battery-powered radio sets.
The participating stations were:
• WCAP in Washington, DC.
• WEAF in New York, NY.
• WJAR in Providence, RI.
• WNAC in Boston, MA.
• WOO in Philadelphia, PA.
• WGY in Schenectady, NY.
• WGR in Buffalo, NY.
• KDKA in Pittsburgh, PA.
• WSB in Atlanta, GA.
• WLW in Cincinnati, OH.
• WGN in Chicago, IL.
• KSD in St. Louis, MO.
• WDAF in Kansas City, MO.
• WLAG in Minneapolis, MN.
• WOAW in Omaha, NE.
• WFAA in Dallas, TX.
• KLZ in Denver, CO.
• KGO in San Francisco, CA.
Almost a hundred years ago, our nation successfully showcased its technological prowess.
Minneapolis Washburn Crosby Company, a flour mill, acquired WLAG’s radio license and, during Oct. 2, 1924, launched WCCO.
Minnesota’s first radio station with a news department, WAMD, began broadcasting June 30, 1925.
NBC and CBS radio began broadcasting in 1926 and 1927, respectively.
In 1928, the radio station WAMD became KSTP.
Television broadcasting soon followed.
On Feb. 21, 1940, Lowell Thomas hosted the first regularly scheduled television news broadcast through experimental NBC television station W2XBS in New York City.
On Sept. 4, 1951, President Harry Truman made the first-ever coast-to-coast television broadcast. According to The New York Times, 94 of the country’s 107 stations aired it in 52 cities.
On the evening of Thursday, Sept. 12, 1924, the radio broadcast of the National Defense Test was recorded by AT&T’s subsidiary, Western Electric, directly from the telephone lines.
The 90-minute high-quality audio recording is preserved in the Internet Archive’s digital library at https://tinyurl.com/radiodefensetest.
