With which of the following three-note sequences does the National Broadcasting Company (NBC) use as an “audio trademark”?

Atlanta’s WBS (740 AM) “Red Network” radio station first used the chimes. NBC started broadcasting in 1926 and established Red and Blue Networks in 1927. A Red Network executive heard the chimes while listening to a Georgia Tech football game and asked to use the sequence nationally.

NBC began to use the chimes in 1931. Later the US Patent and Trademark Office accepted the sequence as the first audio trademark.

NBC still uses the distinctive three-note chimes. In 1985, Composer John Williams incorporated them into “The Mission”, which he wrote as the theme for its television program, “NBC Nightly News”. Parts of that composition are still broadcast, and the sequence is used elsewhere, as well.

Before NBC was created, the Radio Corporation of America purchased two independent radio stations. In 1926, RCA established a new company division, NBC. RCA held controlling interests in the company, holding 50% of the shares, while Westinghouse owned 20% and General Electric Company owned 30%. Despite GEC part-ownership, the sequence has nothing to do with the company.

The apostrophe above a musical note indicates a musical “inversion”. In this case, the inversion has to do with changing octaves while retaining pitch. For example, in G-E’-C’, the E is an octave lower than the G and the C is an octave lower than the E.