chime sets manufactured by the J.C. Deagan Company of Chicago. Additional reports state that the initial sequence was G-C-F-E-G-C-E, which became G-C-G-E and then just G-E-C. November 29, 1929 is sometimes reported to be the date that the three-tone sequence was adopted; however, the longer intervals were still in use until 1931, according to surviving network recordings. The use of signalling tones to indicate the end of a program would be unique to the NBC networks. The CBS Radio network, founded in 1927, never adopted anything similar, instead keying its network switching to the standard phrase "This is the Columbia Broadcasting System". Initially NBC had two national networks, the NBC Red Network and the NBC Blue Network, however the Federal Communications Commission (FCC) was unhappy with this and worked to eliminate the common ownership. In late 1942 Phillips Carlin became vice president of programming at the soon-to-be independent Blue network, which later became the American Broadcasting Company (ABC). One of his first decisions was whether to adopt "a new set of chimes (as distinguished from the NBC chimes now in use)", and the choice was to instead end their use on the Blue network. However, the remaining NBC network operations considered the chimes to be an important part of their corporate identity. In 1942, NBC estimated that the average listener heard the tones 16 times a day, while annually there were nearly 20 billion impressions worldwide. Additional origin explanations Once the NBC chimes became established, a few claimants appeared who stated they were the original inspiration for the practice. However, like the earliest days of the NBC chimes history, there is very little information available to evaluate these claims. One assertion is that the three notes really did stand for "General Electric Company", because it had been the practice to play the keys G-E-C on a piano at WGY, a GE-owned station in Schenectady, New York. A further claim for WSB in Atlanta is that, in addition to being the first station to adopt a three-chime signature, it was directly responsible for NBC's chimes. This explanation states that, as an NBC affiliate, WSB was hosting a network broadcast of a Georgia Tech college football game, and NBC staff at the network's New York City headquarters heard the WSB chimes, which prompted them to ask permission to adopt it for use by the national networks. Rangertone chime machine The original chimes