In November 1920, the Westinghouse Electric & Manufacturing Company established its first broadcasting station, KDKA, located at its plant in East Pittsburgh, Pennsylvania, to promote the sales of it radio receivers.
This initial station proved successful, so in 1921 the company developed plans to set up additional stations in major population centers, including WJZ in Newark, New Jersey (now WABC in New York City), and WBZ, originally in Springfield, Massachusetts, and now in Boston.
It also wanted to start a station in Chicago.

The Westinghouse station was first licensed on November 15, 1921, as Chicago's first broadcasting outlet, with the randomly assigned call letters of KYW.
 At first, it was jointly operated by Westinghouse and Commonwealth Edison, with Westinghouse later taking over as sole operator.
Through the financial support of Samuel Insull, and the cooperation of Mary Garden, director general of the Chicago Opera Company, KYW's initial broadcasts consisted of the opera company's entire six-day-a-week winter season schedule.
Ten microphones were installed across the Chicago Civic Auditorium stage, with equipment for switching between them as needed.
After the close of the opera season, KYW installed a studio in the Commonwealth Edison building, and began producing additional programming.
By fall of 1922 the station was operating for twelve hours a day.

In 1927, Westinghouse affiliated its four radio stations (KYW, KDKA in Pittsburgh, WBZ in Springfield and WBZA in Boston) with the National Broadcasting Company's (NBC) Blue Network, originating from WJZ in New York City, which had been transferred from Westinghouse to the Radio Corporation of America (RCA) in 1923.
Westinghouse had been a founding partner of RCA, NBC's original parent company.

In 1923, Westinghouse established a station, KFKX in Hastings, Nebraska, located near the center of the country.
The station was designed to serve a dual purpose, of providing an agricultural service, and for testing the practicality of using shortwave transmitters to link together radio networks, with KFKX receiving much of its programming by shortwave from KDKA in Pittsburgh.
In 1928 the project was abandoned, although it was announced that the KFKX programming was being consolidated with KYW.
Westinghouse now controlled two stations in addition to KYW in the Chicago area: KFKX and WEBH.
On September 1, 1928 the Federal Radio Commission (FRC) ordered that their operations should be consolidated.
WEBH was deleted, and the other two stations were merged, with a dual call letter assignment of KYW-KFKX, although the latter call sign would be rarely if ever used.

In 1929, KYW's transmitter was moved from the top of Chicago's Congress Hotel to west suburban Bloomingdale Township.

On May 15, 1933, after the FRC requested that stations using only one of their assigned call letters drop those that were no longer in regular use, KFKX was eliminated and the station reverted to just KYW.
In November 1920, the Westinghouse Electric & Manufacturing Company established its first broadcasting station, KDKA, located at its plant in East Pittsburgh, Pennsylvania, to promote the sales of it radio receivers. This initial station proved successful, so in 1921 the company developed plans to set up additional stations in major population centers, including WJZ in Newark, New Jersey (now WABC in New York City), and WBZ, originally in Springfield, Massachusetts, and now in Boston. It also wanted to start a station in Chicago.
The Westinghouse station was first licensed on November 15, 1921, as Chicago's first broadcasting outlet, with the randomly assigned call letters of KYW.  At first, it was jointly operated by Westinghouse and Commonwealth Edison, with Westinghouse later taking over as sole operator. Through the financial support of Samuel Insull, and the cooperation of Mary Garden, director general of the Chicago Opera Company, KYW's initial broadcasts consisted of the opera company's entire six-day-a-week winter season schedule. Ten microphones were installed across the Chicago Civic Auditorium stage, with equipment for switching between them as needed. After the close of the opera season, KYW installed a studio in the Commonwealth Edison building, and began producing additional programming. By fall of 1922 the station was operating for twelve hours a day.
In 1927, Westinghouse affiliated its four radio stations (KYW, KDKA in Pittsburgh, WBZ in Springfield and WBZA in Boston) with the National Broadcasting Company's (NBC) Blue Network, originating from WJZ in New York City, which had been transferred from Westinghouse to the Radio Corporation of America (RCA) in 1923. Westinghouse had been a founding partner of RCA, NBC's original parent company.
In 1923, Westinghouse established a station, KFKX in Hastings, Nebraska, located near the center of the country. The station was designed to serve a dual purpose, of providing an agricultural service, and for testing the practicality of using shortwave transmitters to link together radio networks, with KFKX receiving much of its programming by shortwave from KDKA in Pittsburgh. In 1928 the project was abandoned, although it was announced that the KFKX programming was being consolidated with KYW. Westinghouse now controlled two stations in addition to KYW in the Chicago area: KFKX and WEBH. On September 1, 1928 the Federal Radio Commission (FRC) ordered that their operations should be consolidated. WEBH was deleted, and the other two stations were merged, with a dual call letter assignment of KYW-KFKX, although the latter call sign would be rarely if ever used.
In 1929, KYW's transmitter was moved from the top of Chicago's Congress Hotel to west suburban Bloomingdale Township.
On May 15, 1933, after the FRC requested that stations using only one of their assigned call letters drop those that were no longer in regular use, KFKX was eliminated and the station reverted to just KYW.
KYW (AM)