NBC Chimes - History

History

The chimes came to their familiar configuration and sound after several years of on-air development. They were first broadcast over NBC's Red and Blue networks on November 29, 1929. However, there are disagreements about the original source of the idea. One story is that they came from WSB in Atlanta which allegedly used it for its own purposes until one day someone at NBC headquarters in New York City heard the WSB version of the notes during a networked broadcast of a Georgia Tech football game and asked permission to use it on the national network. The NBC chimes were invented by Robert Blanchard.

The company tested the chimes during 1927 and 1928 when it experimented with several possible combinations of notes. The first sequence consisted of the seven notes G-C-F-E-G-F-E. However, since the original NBC chime machine was an actual set of chimes which the announcer would play 30 seconds before the end of every half-hour to signal the end of a program, it was left to the announcers to play this trademark sequence without error, which was unavoidable with such a lengthy cue. The chime sequence was shortened to G-C-F-E and then, on November 29, 1929, the cue was shortened for the final time, and the three well-known notes G-E-C were heard on NBC radio for the first time.

Despite the relative simplicity and efficiency of the new, shorter chime sequence, problems still existed in other musical aspects of the sequence, such as the tempo, rhythm, and volume at which it was played, as well as the musical tone of the set chimes. Therefore the NBC chimes were mechanized in 1932 with a unit that could play the sequence perfectly and consistently. Richard H. Ranger, a former Radio Corporation of America (RCA) engineer who also invented an early form of the modern fax machine, invented the NBC chime machine that generated the notes by means of finely tuned metal reeds that were plucked by fingers on a revolving drum, much like a musical box.

NBC had several of these chime machines made which they set up at major network locations across the country, including Los Angeles, New York, Chicago, and San Francisco (which actually had two machines, a main one and a backup.) It is estimated that no more than a dozen of these machines were ever made, and even fewer are currently in existence.

The technical purpose of the mechanical chimes was to send a low level audio signal of constant amplitude that would be heard by the various switching stations manned by NBC and AT&T engineers, but not disturb the listening audience. This would serve as the system cue for switching the myriad local stations between the NBC Red Network and NBC Blue Network feeds as scheduled, as well as signalling the pause for local station identification immediately thereafter. In essence, it was the audio equivalent of a traffic signal. Because of fears of offending commercial sponsors by cutting their live network programs off in mid-sentence, the mechanized chimes were always rung by an announcer pushing a button in conjunction with the program’s conclusion; they were never set to an automatic timer, although heavy discussions on the subject were held between the Engineering and Programming departments throughout the 1930s and 1940s.

On November 20, 1947, NBC filed with the U.S. Patent and Trademark Office to make the chimes a registered service mark for identification of radio broadcasting services, the first such audible service mark to be filed with that office. Registration was granted on April 4, 1950; the registration number was 0523616, serial number 71541873. This registration expired on November 3, 1992, as NBC Radio became part of broadcasting history. However a separate service mark registration was made in 1971 for identification of television broadcasting services (serial 72349496, registration 0916522). While this registration is still active, the chime was heard for the final time on the NBC television channel in 1976, the 50-year anniversary of the chime; the chime is now used only for various smaller purposes on the channel.