Clear-channel Station - History

History

For the U.S., a form of clear channels first appeared in 1922 when the Commerce Department moved stations which had all used three (initially two) frequencies (two for entertainment stations, one for "weather and crop reports") onto 52 frequencies. Two were used for all low-power stations and the large stations each got their own frequency. A few frequencies were used on both the East and West coasts, which were considered far enough apart to limit interference. At this time large stations were limited to 1000 watts and some licences were revoked.

On 11 November 1928, the United States implemented General Order 40, which classified each allocation in the AM band as either Local, Regional or Clear. The classification system considered stations in Canada as well. Gradually maximum power was increased to 50,000 watts (with some short lived experiments with 250–500 kilowatt "super-power" operation). This system was continued in the 1941 NARBA system although almost all stations shifted broadcast frequencies. The FCC's intent behind licensing 50,000 watt clear channel stations was to provide reliable radio service to the thousands of Americans who lived in the vast rural areas of the United States. As a result, these stations usually reached large portions of North America at night. Radio fans often call such stations "flamethrowers" or "blowtorches" because of their power.

As early as the 1930s, debate raged in Washington, D.C., and in the U.S. broadcasting industry over whether continuation of the clear-channel system was justifiable. The licensees of clear-channel stations argued that, without their special status, many rural areas would receive no radio service at all. Rural broadcasters pointed out that most of the clear-channel stations were licensed to serve large cities on the two coasts, which made little sense for a service that was meant to provide radio to the vast rural areas in the middle of the country. The clear-channel licensees requested that the power limit on the "I-A" channels in the U.S., set at 50 kW by the FCC, be lifted entirely. They pointed to WLW's successful experiments before the war, and in later years successful implementation by state broadcasters in Europe and the Middle East, as evidence that this would work and improve the service received by most Americans. Other broadcasters, particularly in the western states, argued to the contrary—that if the special status of the clear-channel stations were eliminated, they would be able to build facilities to provide local service to those rural "dark areas".

One of the most outspoken of the small-town broadcasters, Ed Craney of KGIR in Butte, Montana, went so far as to apply to move his station, then on the 1370 kHz regional channel, to a class I-A signal on 660 kHz, asking the FCC to downgrade the NBC New York flagship, WEAF, to make way for the Butte station. The FCC denied Craney's petition.

In 1941, several existing clear-channel stations applied for power increases to between 500 and 750 kW; dissemination of national defense information is cited as one reason this would be in the public interest. The FCC's engineering department presented a report on a complete reorganization of the clear-channel service in October, 1941; the report considered the possibility of "some 25 superpower stations of 500,000 watts or more, strategically located to provide maximum service" (as Broadcasting described it), and suggested that stations would have to be relocated away from the east and west coasts in such a scenario, as coastal stations waste energy over the oceans. One complication the FCC considered was the "Wheeler Resolution", passed by the United States Senate in 1938, expressing the view of the Senate that radio stations should be limited to a maximum power of 50 kW.

One station, KOB in Albuquerque, New Mexico, fought a long legal battle against the Federal Communications Commission (FCC) and New York's WABC for the right to move from a regional channel to a clear channel, 770 kHz, arguing that the New York signal was so weak in the mountain west that it served no one. KOB eventually won the argument in the late 1960s; it and several other western stations were allowed to move to eastern clear channels. (Western clear channels, like 680 in San Francisco, California, had been "duplicated" in the eastern states for many years.) These new class II-A assignments (in places like Boise, Idaho; Las Vegas and Reno, Nevada; Lexington, Nebraska; Casper, Wyoming; Kalispell, Montana; and others) began what would later be called "the breakdown of the clear channels". The class I-A station owners' proposal to increase power fifteenfold was not immediately quashed, but the new II-A stations would make it effectively impossible for stations on the duplicated channels to do so, and the owners eventually lost interest. That proposal was finally taken off the FCC's docket in the late 1970s.

On May 29, 1980, the FCC voted to limit the protection for the twenty-five clear channel stations to a 750-mile radius around the transmitter. Those stations outside the area of protection were no longer required to sign off or power down after sundown.

In 1987 the FCC changed its rules to prohibit applications for new "class-D" stations. (Class-D stations have night power between zero and 250 watts, and frequently operate on clear channels.) However, any existing station could voluntarily relinquish nighttime authority, thereby becoming a class-D, and several have done so since the rule change.