[6] In early 1922, AT&T announced the establishment of a "toll" station in New York City and its intention to develop a nationwide commercial radio network using their Bell System infrastructure.

[9][10][11] The first continuous link was established on July 1, 1923, when Colonel Edward H. R. Green arranged for AT&T to provide WEAF programming for rebroadcast by his station, WMAF at South Dartmouth, Massachusetts.

[6] One early success for the "WEAF chain" was The Eveready Hour, the first sponsored program to be broadcast over a radio network, paid for by the National Carbon Company.

[30] The first RCA network broadcast occurred on November 17, 1923, when WJZ rebroadcast play-by-play of a Princeton Tigers–Harvard Crimson college football game over GE's WGY in Schenectady, New York, linked together via the Western Union system.

[38][39] Variety regarded the sale as an economical one for AT&T, as the WEAF chain generated an annual income of $500,000, with little hope of turning a profit, "which even an affluent corporation like (AT&T) takes into consideration".

[47] This broadcast, which included a remote link from KYW in Chicago, was coordinated through WEAF, and carried by twenty-two eastern and Midwestern stations, located as far west as WDAF in Kansas City, Missouri.

[50] The debut program, sponsored by the Victor Talking Machine Company,[b] was carried on both chains and subsequently alternated between "red" and "blue" on a weekly basis.

[1] As 1927 began, KFI in Los Angeles and KPO in San Francisco were successfully transmitting live programming to a regional network of their own, dubbed the "Orange Network",[58] notably originating play-by-play of the 1927 Rose Bowl[59] and a live performance of Carmen from the Philharmonic Auditorium on January 23, 1927; the latter broadcast was additionally relayed over CNVR in Vancouver, WAMD in Minneapolis, and WGY.

[64] At the same time, NBC began acquiring radio stations to extend its reach, beginning with KGO and KOA in Denver, Colorado, from GE in March 1930.

[73] RCA agreed to a lease in May 1930 as the lead tenant for 30 Rockefeller Plaza which was still under construction, including a studio complex for NBC and theaters for RCA-owned RKO Radio Pictures.

[89] The network provided a rich variety of classical concert broadcasts, including performances by the Metropolitan Opera (1931–1940)[90] and the NBC Symphony Orchestra (1937–1954) conducted by Arturo Toscanini.

Among the band leaders with regular time slots on NBC were Carmen Cavallaro, Nat King Cole, Xavier Cugat, Tommy Dorsey, Eddy Duchin, Benny Goodman, Stan Kenton, Guy Lombardo, Glenn Miller, Leo Reisman, and Paul Whiteman.

[111] Following the lead of WNBT, NBC filed applications for multiple FM and television stations as adjuncts to their radio properties as early as 1943, including for TV outlets in Denver and San Francisco.

[2][124] Paley personally worked to woo the performers, while Sarnoff professed his indifference to the defections, stating at an annual meeting that "Leadership built over the years on a foundation of solid service cannot be snatched overnight by buying a few high-priced comedians.

[129] Texaco Star Theater, an umbrella title for various radio variety shows from 1938 to 1949, migrated to NBC-TV in 1948 with Milton Berle as host, becoming both a cultural landmark and the first successful hit program in the medium.

Hosted by stage actress Tallulah Bankhead, it harked back to radio's earliest musical variety style along with sophisticated comedy and drama.

[131] Despite critical praise, The Big Show's initial success failed to last as NBC cancelled it after only two years, purportedly losing a million dollars on the project.

[137][138] The acquisition of WJAS was to offset KDKA's defection from the network several years earlier, while WKNB was included as part of the sale of its sister television station.

NBC ended its radio association with baseball after the 1975 season in order to clear space for its 24-hour "News And Information" service programming, though it continued broadcasting on its television network until 1989 (while splitting coverage with ABC in all but the first year of that period).

[148] Monitor boasted a variety of hosts including such well-known television personalities as Dave Garroway, Hugh Downs, Ed McMahon, Joe Garagiola and Gene Rayburn.

The potpourri also tried to keep vintage radio alive in featuring segments from Jim and Marian Jordan (in character as Fibber McGee and Molly), Ethel and Albert and iconoclastic satirist Henry Morgan.

[149] Monitor is credited for succeeding in an era where television became the dominant entertainment medium,[149] but after the mid-1960s, local stations with established music formats—especially in larger markets—became increasingly reluctant to run network fare, dropping the program block outright,[150] including flagship WNBC.

[152] From that point onward, the NBC Radio Network's main lineup consisted of hourly newscasts and commentary segments, plus religious programs and Meet the Press on Sundays.

[161] In 1979,[162] NBC launched The Source, a secondary network that targeted younger listeners, providing news, short features and music specials to FM rock stations.

[163] The Source also featured a talk show hosted by sex columnist Ruth Westheimer[164] beginning in 1984, which originated at NBC's New York FM station WYNY.

Headlined by advice host Sally Jessy Raphael and personal finance talker Bruce Williams, NBC Talknet was largely inspired by the success of the all-night Larry King Show on Mutual.

[169] NBC Radio Entertainment was established in December 1984 to handle the distribution of Jazz with David Sanborn and Live From the Hard Rock Cafe with Paul Shaffer, along with an oldies show hosted by WNBC's Soupy Sales.

[182] Following the sale, NBC Radio added one long-form program to their lineup—a daily talk/variety show hosted by Steve Allen based from WNEW that debuted in October 1987.

[195] By January 1989, Westwood One announced NBC Radio News would move to Mutual's Arlington, Virginia, facility;[196] engineering operations followed[197] along with the affiliate relations department.

[197] NBC Talknet's operations also moved to the Arlington facilities in 1992[201] and largely continued until 1993, when it was limited solely to Bruce Williams' weeknight show—ceding the other three-hour slot to Jim Bohannon's Mutual talk show[202]—and was eventually rebranded as a Westwood One program.