Chapter 1 – FM BROADCASTING

Version: 1.0 Project Thesis Report – MBA (I.T) Date: 2011-10 (YYYY-MM) Chapter 1 – FM BROADCASTING GLANCE: This chapter covers most common definitions and different terms of F.M broadcasting like terminology, broadcast bands, History of F.M broadcasting, distance covered by an F.M radio station, adoption of F.M radio technology, F.M broadcasting in Pakistan, Major F.M Channels in Pakistan. The history of F.M broadcasting is briefly discussed to give an idea of origin, adoption and innovation of technologies in advancing the present concepts of F.M radio station. Most of the countries expanded their use of FM through the 1990s. Because it takes a large number of FM transmitting stations to cover a geographically large country, particularly where there are terrain difficulties, FM is more suited to local broadcasting than for national networks. In such countries, particularly where there are economic or infrastructural problems, "rolling out" a national FM broadcast network to reach the majority of the population can be a slow and expensive process. 3 5 Version: 1.0 Project Thesis Report – MBA (I.T) Date: 2011-10 (YYYY-MM) FM BROADCASTING 1.1 INTRODUCTION FM broadcasting is a broadcast technology pioneered by Edwin Howard Armstrong that uses frequency modulation (FM) to provide high-fidelity sound over broadcast radio. 1.2TERMINOLOGY The term "FM band" is effectively shorthand for "frequency band in which FM is used for broadcasting". This term can upset purists because it conflates a modulation scheme with a range of frequencies. 1.3BROADCAST BANDS Throughout the world, the broadcast band falls within the VHF part of the radio spectrum. Usually 87.5 to 108.0 MHz is used, or some portion thereof, with few exceptions: • In the former Soviet republics, and some former Eastern Bloc countries, the older 65–74 MHz band is also used. Assigned frequencies are at intervals of 30 KHz. This band, sometimes referred to as the OIRT band, is slowly being phased out in many countries. In those countries the 87.5–108.0 MHz band is referred to as the CCIR band. • In Japan, the band 76–90 MHz is used. The frequency of an FM broadcast station (more strictly its assigned nominal centre frequency) is usually an exact multiple of 100 KHz. In most of the Americas and the Caribbean, only odd multiples are used. In some parts of Europe, Greenland and Africa, only even multiples are used. In Italy, multiples of 50 KHz are used. There are other unusual and obsolete standards in some countries, including 0.001, 0.01, 0.03, 0.074, 0.5, and 0.3 MHz. 1.4History of FM Broadcasting Some aspects of radio history are open to debate, and may always be – was KDKA really the first station, or was it WWJ, or perhaps, 1XE/WGI? 3 5 Version: 1.0 Project Thesis Report – MBA (I.T) Date: 2011-10 (YYYY-MM) But in the matter of early FM, this much is generally agreed upon: we owe its development in New England to two men – the inventor Edwin Howard Armstrong, and the business executive who believed in and supported his work – John Shepard 3rd. When Armstrong's former friend and colleague David Sarnoff turned away from a commitment to FM, it was Shepard who offered encouragement. Always quick to spot a trend, Shepard believed that FM could be beneficial and profitable; many station owners were threatened by FM, fearing it would hurt their AM operations, but Shepard had no hesitation in befriending Armstrong and investing in FM. Shepard put the power and prestige of the Yankee Network at Armstrong's disposal and planned to bring FM broadcasting to greater Boston. In the spring of 1937, Shepard applied for a permit for a 50-kW FM station in Paxton. In an article he wrote for FM Magazine in March of 1941, Yankee Engineering Vice President Paul DeMars recalled that the plan was initially beset with problems: "Delays in obtaining a suitable site, held up construction for over a year, but in October of 1938, work was begun. When this project was planned, no 50-kW equipment had been built for the frequencies assigned to FM experimentation. Furthermore, no antenna system had been designed or constructed with radiating efficiency high enough to insure the desired performance." Undaunted, the construction team built a road through what had been woods and pastures, to the top of Asnebumskit Hill, and embarked on erecting what would become W1XOJ, the first FM station in Massachusetts. As DeMars mentioned in his article, since 50-kW transmitters for FM were still being perfected, the new station did not go on with full power. Its first broadcasts were at about 2 kW. (The Paxton site is still used for FM broadcasts, by an indirect descendant of that station, now WAAF. When the Worcester Telegram & Gazette decided to build their own FM station, W1XTG, they chose adjacent Little Asnebumskit Hill; that station is now WSRS and is still in the original location.) The Boston media tried to explain what was going on, since the average person might be confused by so many new developments. The Boston Post noted in a May, 1939 article that within weeks, New England would hear "a radically new and different broadcasting service that may prove to be revolutionary... the new system not only requires a new type of transmitter but it also requires a new type of radio receiver. Transmission will not be in the regular broadcast band but on ultra high-frequency, 43 megacycles or seven metres approximately." The Post informed its readers that W1XOJ would have its transmitter "on top of a hill whose summit is 1375 feet above sea level. The antenna mast is 400 feet high and supports a special array called a 'turnstile'. The purpose of this array is to direct the radiation toward the horizon and to suppress skyward radiation". Unfortunately, buried in the glowing reports of the near completion of the Paxton site was the news that the Yankee Network programming Shepard wanted to broadcast from Boston was not able to reach Paxton; thus, a relay station 3 5 Version: 1.0 Project Thesis Report – MBA (I.T) Date: 2011-10 (YYYY-MM) (called at first W1XOK, then WEOD) was built; it had 250 Watts, and was located at the Yankee Network studios on Brookline Avenue. What the Boston media did not mention was that WBZ was not amused. Westinghouse and Shepard had long been in competition for advertising dollars. Now, the Westinghouse engineers felt they were being upstaged by Shepard's ability to get his name (and the names of all his engineers) in print as innovators in FM. I have copies of several letters sent back and forth between WBZ's chief engineer and Shepard's, with claims and counter-claims. WBZ wanted to enter into the FM area too, but clearly, Shepard was scoring a major publicity coup, and the Boston newspapers were giving him lots of ink. (In fairness, it should be pointed out that for a time during the early 1930's, during the 'Press-Radio War', the print media had been Shepard's bitter enemies; but the sudden arrival of a new and exciting technology plus the fact that Shepard was instant copy, always ready with an event or a quote, made even former rivals follow him around to see what FM could really do.) Prior to W1XOJ's first broadcast, Shepard---in conjunction with the Institute of Radio Engineers---scheduled a demonstration of FM, to which he invited his competitors from other stations. The demonstration, which took place on May 26, 1939 at Northeastern University, was also attended by several hundred college professors, engineers, scientists, and technicians, as well as one very annoyed chief engineer from WBZ. In a letter to the home office several days after, WBZ Plant Manager Dwight Myer called the event basically a waste of time and claimed to be totally unimpressed. He closed his letter with these comments: "It is not frequency modulation itself that I am belittling but the meeting. The talks were non-technical, and in my opinion, it was engineered as a mutual publicity stunt for John Shepard and Major Armstrong." Publicity stunt or not, the Boston media expressed great enthusiasm. The Post that Sunday headlined "Engineers Hail Noiseless Radio" and went on to describe how the audience listened with amazement to a variety of source material, all of which came through with incredible clarity. In the talk which Armstrong gave before the demonstration, he did in fact thank Shepard for his support, but he also explained that it had been Paul DeMars who had first come to believe in FM and who then persuaded Shepard to become involved. On July 24, 1939, W1XOJ began a schedule of 16 hours a day on the air (8 AM to midnight). The power was soon boosted to 30 kW, but then in mid- January of 1940, a violent ice storm did serious damage to the transmitting antenna, and a temporary antenna was called into service. It would take another year before Shepard's dream of a 50-kW FM became a reality, on January 15, 1941. But Shepard had another dream too---an FM network for 3 5 Version: 1.0 Project Thesis Report – MBA (I.T) Date: 2011-10 (YYYY-MM) New England. There was a 500-Watt Weather Service station (W1XOY) atop Mt. Washington in New Hampshire, and he hoped to convert it into his second FM. Broadcasting the Yankee Network programs just as W1XOJ did, this new station would be capable of reaching a very underserved area of Northern New England, an audience he estimated at nearly a million people.

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