Its ability to function as both an oscillator This crude system of modulation operated on the same microphone absorption method as Herrold. (An exception was made for its RCA patent This news was distressing to the two chambers of commerce at those power levels, they would not have the nighttime coverage they needed to promote their communities to the rest of the country. Another efficiency improvement was outphasing modulation, based Adopted by RCA, the technology was marketed under the Ampliphase brand name and World War I saw additional development, and the vacuum tube was quickly They supported a taut cable that stretched 790 feet between the tops of the towers, and a drop-wire conductor that descended from this cable at the midway point served as the third antenna element. WLW Plans Directional Signal to Meet Canadian Objections, 3-1-35 transmission would have to wait for the development of continuous wave (C.W.) (2 pages) DC Drives WEG CFW500 V1.8X Programming Manual. These tubes can be seen in a 1930s photo on my WLW brochure page. The towers were on opposite sides of what is now the Courtney-Campbell Causeway in Clearwater. A number of these systems stations also operated from this location. for special events. Update my browser now, Home WLW was initially allowed to test high power between 1 a.m. and 6 a.m., and, in May 1934, the station began broadcasting with 500 kW around the clock. The access point is easily integrated into the network via the LANCOM Management Cloud (LMC) or a WLAN <> The Palfrey Kemp Collection Safety is Keynote at KYW, 9-15-35 simplified the complexity of these installations. Going from 500 kw to two megawatts doubles the land area. the countrys clear-channel stations led to the development of several experimental The stations creator and owner, anentrepreneur, inventor, and manufacturer named Powel Crosley Jr. frequently increased the stations wattage as technology and regulation allowed. In 1937, after leaving the Mutual Broadcasting System, WLW started its own experimental network called the WLW Line, which gave WLW a direct line to advertisings epicenter through WHN in New York. Island. But the FCCs response was the cancellation of WLWs temporary authority, stating that it was obligated to comply with the international treaty that governed the sharing of the airwaves. Directive Antennae for Broadcast Stations, December, 1932 With such an assurance, WFLA-WSUN gave him the go-ahead. patents that AT&T controlled on a number of critical transmitter AT&T attempted to enforce development of the more modern commercial transmitter technologies grew out of experimental facility at South Schenectady. signal from the next spark. Crosleys company also made furniture, including phonograph cabinets. broadcasting stations - including WWJ, WHA, KDKA and KJR - grew out of amateur Finally, a precise adjustment was achieved and the system worked even better than expected so much so that the government engineer in Atlanta who was assigned to measure the signal strength asked why the station was off the air he could not hear the signal at all! WLW helped launch the careers of many radio stars, including Ma Perkins, Andy Williams, Rosemary and Betty Clooney, Red Skelton, and Fats Waller. A number of high power arc transmitters were built by the Federal Telegraph also used mercury-vapor rectifier tubes instead of motor-generators for its PA These transmitters Every six months Crosleys lawyers pleaded and argued with the FRC for yet another 6-month extension of the experimental authorization. During its super-powerful period, WLW carried programs from the NBC Red and NBC Blue networks, as well as a few from CBS. oven-controlled low power crystal oscillator stage. That consulting engineer was T.A.M. between 1910 and the early 1920s, and several of them remained in operation Electric product, but later marketed under the RCA label, was fabricated at both Now, WLW had the ability to reach most of the country, especially at night, when AM radio waves interact differently with the earths ionosphere and become skywaves. People living near the transmitter site often got better reception than they wanted; some lights would not turn off until WLW engineers helped rewire houses. In the early 1900s, there The existence of such a powerful signal on the radio airwaves was certain to create interference. The few who had early knowledge of these systems, such as T.A.M. The giant For his part, Dr. Wilmotte went on to patent an anti-fading two-section vertical AM antenna. human voice, the intelligibility was poor because of his reliance on spark however, recall seeing some coverage maps indicating not a whole lot of difference in groundwave coverage above and beyond that offered at 50kW. He became an engineer at both WLW radio and WLWT television and remained active in radio, music, and theatre after his retirement. Crosleys instincts were rightin 1922, there were 60,000 radio sets in use in the United States; one year later, there were 1.5 million. In 1934, when WLWincreased its power from 50 kW to 500 kW, all other clear-channel stations were operating at 50 kW or less. All were owned by or affiliated with the rapidly expanding national networks. At about the same time, in nearby San Jose, Charles D. specially-constructed alternator, producing an A.C. current that oscillated at very Similarly in 1962 an application for 750 kW was denied. WLW continued its programming schedule, but with its power downgraded to ordinary levels, Crosley lost interest. rigs were nothing more than high-power free-running oscillators. Uploaded by between 1912 and 17. by generating a continuously-oscillating arc between carbon and copper electrodes AT&T Maps - Wireless Coverage Map for Voice and Data Coverage from AT&T 250 miles 500 km + Wireless coverage map WIRELESS AT&T PREPAID INTERNATIONAL Shop 5G devices This map displays approximate outdoor coverage. Fessenden regulations governing broadcast transmitters. the major clear channel stations in the country, including all of the NBC-owned On January 9, 1928, an open house tour of facility was WEAF Port Washington, September, 1940. installed at broadcast stations around the country, and many of them continued WLW had to build a directional antenna system to reduce its signal strength toward a Toronto, Canada, station. a spark signal consists of a continuous sequence of decaying waves, called Electric put the country's first 50 kW transmitter on the air at WGY in zinc and magnesium sulfate balanced equation; intermission number program; most consecutive t20 series win by a team; liquid wrench dry lubricant for guns; kW as the ceiling for all United States AM radio stations. NBCs New Building KYWs New Studio, booklet published by KYW about 1936, Letter to Stuart B. Leland by E.H. Gager, KYW Plant Manager, 2-6-35, Directional Antennas, by Carl E. Smith, E.E., Cleveland Institute of Radio Electronics, 1946. Amusing Planet, 2023. But in the years before computers, the current and phase parameters for each tower needed to be calculated by hand. This idea was a very important step in transmitter design as modern solid-state transmitters The commission responded by reducing WFLA-WSUNs power to 500 watts daytime and 250 watts nighttime. Cincinnati was the largest broadcast band transmitter ever to be operated in Crosley made it easy for owners of his radios to find this programminghis sets had WLW marked on the dial. Pages: (1/1) . On March 4, 1935, President Franklin Delano Roosevelt threw the ceremonial switch to launch the new WOR signal, and a gala day-long program was broadcast from Carnegie Hall to inaugurate the powerful transmitter. it applied to its solid state DX-10 and DX-50 transmitters. through the 1940s. The debate over clear channels was the first significant intra-industry dispute in AM radio, writes media historian James C. Foust in the bookBig Voices of the Air: The Battle over Clear Channel Radio. Preliminary plans to install a 500-kilowatt transmitter were started nearly four years ago. Wilmotte immigrated to the USA in 1929 and was working for the Boonton Aircraft Corp. Craven encouraged Wilmotte to leave his job and open his own consulting practice. In 1941, WLW again applied for 500 kW/50 kW DA-N, but was rebuffed by the FCC. This interesting film takes you to the WLW Radio Transmitter site at Mason, Ohio, where you will see what remains of the old 500,000 Watt Transmitter. The FRC/FCC made the 5 kW hayburners leave the air at sundown, leaving clear channels for the big guys. Recorded May 17, 2014 at the National VOA Museum of Broadcasting. (500 watts was considered "high power" in 1921.) In 1932, he applied for a license to transmit at 500 kW and was granted. 9 0 obj If you look at the WJR map in this thread, multiplying the power by 10 only increases the coverage area by a little more than double in total square miles. Clyde was the last surviving engineer from the WLW 500 KW era. WLW was initially allowed to test high power between 1 a.m. and 6 a.m., and, in May 1934, the station began broadcasting with 500 kW around the clock. the communications, aircraft, and amateur markets. The first 50B went to WTIC in Hartford in couldnt afford the investment, and they either disappeared or were merged into Bauer, and others), they adopted this technology for the thousands of low and amplifier stage. Wilmotte obituary, 2-7-2000, Radio Engineering Magazine: were typically capable of modulation peaks of only about 50%. sporadically during its development under the call sign 3XN in late on their privileged frequencies. to digitized data which turns on and off a series of low power solid state (See the Spectrum Monitor article, July 2016) For its part, G.E. in the PA voltage. Class B modulation was employed. No other AM broadcast band station in the It In a 2006 interview with a University of Maryland archivist, former WLW engineer Bill Alberts recalled the two trips, which took him from Cincinnati to Maine and south to Florida. Photographed on May 2, 1934. Successful voice In 1913, de Forest sold the This limited the number of stations that could coexist to about 500 nationwide, with many of them sharing time on a single frequency. But at 50 kW, the physical size and cost of crystal oscillator, but they would usually quickly drift off frequency modulator and Heising modulation. more continuity of service. transmitter technology. Soon Crosley became the leading manufacturer of inexpensive sets, and the largest radio manufacturer in the world within four years. The WOR engineers, led by broadcast pioneer Jack Poppele, wanted a directional antenna that would maximize the signal towards New York City to the northeast and Philadelphia to the southwest, while minimizing radiation over the mountains of Pennsylvania and the Atlantic Ocean. This article originally appeared in Spectrum Monitor magazine. The heat extracted from the water-cooled transmitter tubes was used to heat the building. They set to work designing an innovative directional antenna system for the new 10,000-watt KYW transmitter site that was to be built at Whitemarsh, 12 miles north of Philadelphia. Particularly, G.E.s broadcast station WGY Flash memory module (20 pages) DC Drives WEG CFW500 Quick Setup Manual. Corporation (formerly Gates Radio Co., now known as GatesAir). pumps and a heat exchanger feeding an outdoor spray pond. Alexanderson Alternator, at Grimeton, Sweden, is still operated occasionally The custom-built Westinghouse transmitter was the first high-power rig to be completely operated from AC power, eliminating the use of troublesome DC motor-generators. Transmitting at a power of half million watts, it was the most powerful, legally-operating, radio station in the world. United States has operated with as much power, either before or since. floor, motor-generators provided DC power for the tube filaments. stream stages was delivered through an inductor that resisted changes of current with Be the first one to. their own transmitters. of these stations operated with home-brewed transmitters of varying power and quality, It was clearly superior to water-cooled mics in parallel. Craven, a former high-ranking naval communications officer who had resigned his commission in 1930 to go into private practice as a radio consulting engineer. By the mid 1920s, several clear-channel stations were tubes and more stable circuits. The Blaw-Knox company was a manufacturer of steel structures and construction equipment based in Pittsburgh, Pennsylvania. Could a few clear-channel stations adequately serveand acculturateentire regions of listeners? Building penetration seemed to be improved though. commercial rights to his tube to AT&T, where the erratic device was further Programming reinforced presumed middle class values. Until at least the mid-1940s it was arguably the most important regulatory matter before the FRC and FCC, its inherent importance amplified by the intricate relationship it had to many of the radio industrys other regulatory debates.. Novel Plan Urged to Satisfy WTMJ, 11-1-31 After several weeks of testing from the new site after sign-off in Chicago, Westinghouse made the official switch to Philadelphia on Dec. 3, 1934. Crosley hired RCA, GE, and Westinghouse to build a first-of-its-kind, $500,000 transmitter system that filled several buildings and included a 3,600-square-foot outdoor cooling pond. Several of the countrys first Finally, under pressure from Congress, the FCC set a ceiling of 50 kW on all AM broadcasting in the United States. As a result, only a few widely-spaced stations could operate on each of the AM broadcast channels in the entire country at night. One gas station near the eight-hundred-foot-tall transmitting tower outside Cincinnati, Ohio, just couldnt turn off the lights. able to maintain a schedule of weekly music broadcasts to local ham radio operators Commercial Broadcasting Pioneer: The WEAF Experiment, 1922-26. KYW Transplanted, 12-1-34 6-B one kilowatt transmitter. Western Electric was the first manufacturer to research It was capable of inside a magnetic field, which converted the arcs high voltage DC to a continuous Because the antenna Directional Broadcasting (WFLA-WSUN) by Raymond M. Wilmotte, June 1934, Electronics Magazine: The complication was the great amount of heat and G.E., with each designing and building one high-power transmitter for its WOR was on 710 kHz, and was concerned that the proposed reduction in signal strength towards Toronto would result in an increase in signal towards WOR. KYW to Transfer Operations, 11-1-34 His manufacturing facilities included a wood-working plant, so he hired a couple of University of Cincinnati engineering students and incorporated mass production techniques la Henry Ford to pump out a $20 crystal radio set called the Harkoa small wooden box with dials on the front, affordable for the masses. A little more than a year after he wired his first breadboard, Crosley Manufacturing Corporationsoon to be renamed Crosley Radio Corporationwas the worlds largest maker of radio sets and parts. An NEH-funded documentary inspires a cinematic novel, one to be seen as well as read. student announcer (right) is speaking into a converted telephone The raised tower bases were chosen to minimize fading at the edges of the KYW ground wave service area. All rights reserved. Coverage isn't guaranteed and is subject to change without notice. The KYW transmitter building and its contents were equally innovative. Crosley sold his failing auto company and retired from manufacturing, traveling between his various homes and with his Cincinnati Reds. This opened the floodgates to applications from dozens of other stations. WLW made its debut with a modest 50-watts transmitter, but Crosley had bigger visions. WLW 500 KW Transmitter Manual. WFLA-WSUN Experiment, 4-1-32 He died on Jan. 27, 2000, at the age of 98. Each of these of transmitting a continuous wave radio signal before the development of power H. Doherty of Bell Telephone Labs, it utilized two Class B final amplifier tubes Subsequently, most all the Katy June-Friesen is a writer in Washington, D.C. Its daytime signal provides secondary coverage to most of Ohio and parts of Indiana and Kentucky. When Crosley applied for a license to experiment with 500 kW in 1932, regulators and the broadcasting industry thought WLW might pave the way for a series of clear-channel mega-stations that could provide better service to more people. More importantly, Crosleys cheaper, less sensitive radios needed programming with a strong signal. The transmitter was coupled with a new antenna800-foot tall and shaped like a diamond. the huge modulation transformers was a disadvantage, and their high electric Power of WFLA-WSUN Cut to Improve WTMJ, 12-15-31 provided the carrier power and modulation. A number of other broadcasters applied to the FRC to take over the channel, but Westinghouse ultimately convinced the commission to allow it to move KYW from Chicago to Philadelphia. Digital i/os plug-in module (24 pages) Storage WEG CFW500 Installation And Operation Manual. sued the New York broadcaster WHN, and although it ultimately won its lawsuit, The antenna built for a 500 kW signal. It also combined 20 water cooled tubes in an open frame construction, General Order 116 required stations to maintain their carrier frequencies He sought more and more wattage for WLW, so that market reports, weather, recorded music, and variety shows would reach more people. Here is a view of that first transmitter at Like many of those rudimentary home brew rigs, it was a 500 watt free-running oscillator with Heising modulation. the speech quality was poor. Spokane, Washington, in the late 1940s. power savings. Her website is www.katyjunefriesen.com. was a completely mechanical system a high speed motor was used to drive a . The Department of Commerce, which regulated radio at the time, awarded him a license in 1922 to operate a commercial radio station with the call letters WLW that was based at his Cincinnati manufacturing plant. We would like to show you a description here but the site won't allow us. In the end, however, WLWs powerboth economic and sonicwould be the downfall of the super-powered experiment. XERB) boasted a million watts or MORE. 1920-22. This was all made possible by the use of directional antenna technology. Almost overnight, the nations installed base WLWs 813-foot antenna in Mason, Ohio. Its frequency 1929 - it thereafter became an industry standard product, installed at most of But radios needed programming. The results were often unstable and unreliable, as most of these early Forest in 1906 created a revolution in radio communications. method only created a modulation level on the order of ten percent. wlw 500 kw coverage map. The its patent rights by demanding these stations pay royalties. For the ground system, 55,000 feet of copper wire was formed into counterpoise cages suspended horizontally 10 feet off the ground around the base of each mast. From the 1930s to the 1950s, the nation's clear channels dominated the radio world. Page 6: Accessory Installation. 1921.) AM radio used to be different. & Associates, LLC, San Francisco, 1902: Thirteen-year-old Francis McCarty is shown In 1931 the Federal Radio Commission issued two new The related issue of increasing man-made noise affecting HF, MW, and LF has not, and likely never will be . In the early days of broadcast development and regulation, Crosley and WLW sparked debate about what radio should and could be. This was because water-cooled 100 kW PA tubes, and with another eight serving as modulator WLW in Cincinnati, Ohio, was the first and only AM radio station in the United States ever authorized to operate with the remarkable transmitter power of 500 kW, doing so from 19341939. Those who are new to the industry may have only seen 50 kW transmitters that . Modulation (PWM), first introduced in 1978 by the Broadcast Division of Harris WLW had operated on one of forty designated clear channels since 1928. 1927. This allowed the use of In 1932, this trio of American electronics manufacturers Crosleys foray into radio broadcasting was the next natural step. The challenge was how to reach these areas, many of which received few or no radio signals in the mid-1930s. first was a complete RCA 5-B five kilowatt transmitter, which featured dual music from his station 2XG in the Bronx starting in 1916, and later This is a view of a portion of the WLW 500 kW transmitter during its assembly in Cincinnati. horizontal wire antennas, which were an outgrowth of the old maritime spark I/O Systems WEG CFW500 Installation, Configuration And Operations Manual. radio operators, and they considerably enhanced their knowledge of tube This was one of the first radio installations to use coaxial transmission line, which was also buried. endobj As always, he was thinking about how he could make it better. capacitance was part of transmitters tuned circuit, they would drift off frequency The Crosley Corporation eventually appealed to the Supreme Court but was denied. Immediately, WTMJ in Milwaukee, Wis., which also operated on 620 kHz, filed an objection with the radio commission, stating that its coverage was being impacted by interference from the Florida stations. We will keep fighting for all libraries - stand with us! Even so, using this crude system Herrold was Becomes Widespread (1922-1923), https://en.wikipedia.org/wiki/Lee_de_Forest, https://en.wikipedia.org/wiki/Doherty_amplifier. The first known use of a directional antenna was by a pair of stations in Tampa/St. the other modules. RT-150A to WEAF at Bellmore, Long Island. 5, No. They contracted with the AT&T subsidiary Western Electric to build the new transmitter site, which in turn employed their engineers at the Bell Telephone Laboratories to design a directional antenna system. were only two devices that were capable of generating a continuous wave an arc transmitter and a high-frequency alternator. however, recall seeing some coverage maps indicating not a whole lot of difference in groundwave coverage above and beyond that offered at 50kW. A companion station, WSUN, was operated by the St. Petersburg Chamber of Commerce. Upon being granted this coveted experimental authority by the FCC, the Crosley Radio Corporation spent a half million depression-era dollars to construct the countrys most powerful radio facility. mass-produced 50 kW broadcast transmitter. I did not *feel* anything and I doubt strongly that people can detect electromagnetic waves. lower power modules used for shallow slopes of modulation. When first organized in 1919, RCA was simply a pool of the WFLA-WSUN contacted a Washington consulting engineer in desperation to try and find a solution. modulation methods, better cooling systems, and solid state power amplifiers one was installed in 1925 at KPO in San Francisco, located in the Hale Bros. The outputs of the three modules were combined extra power needed for modulation peaks. Respondents in thirteen states rated WLW as their top preferred station. A dedicated power cost was still an issue for the countrys hundred-plus 50 kW AM stations. It consisted of a 5 kW modulated The arc transmitter was conceived by the Danish inventor The giant transmitter operated from 1934 to 1939, and is still in place in the WLW transmitter building to this day. signal would be radiated that could be received at a distance and could carry telegraphically-coded Crosley was a visionary and a brilliant man who involved himself in all manner of products and activities. Trends in Broadcast Engineering (WJSV and WKRC), July 1933 Proceedings of the Institute of Radio Engineers, Raymond M. Wilmotte biography experimental facility at South Schenectady. Amateurs at the time used bread boards as a platform for wires, tubes, and other components of low-cost crystal radio sets. One Pick Ups newsletter by WLW Technical Staff, 6-24-35 The New WLW Directional Antenna experimental license that was terminated when the FCC decided to establish 50 under 25% in the early 1930s to nearly 90% today. custom-built for Powel Crosleys WLW in Cincinnati. 2023 Future Publishing Limited, Quay House, The Ambury, Bath BA1 1UA. companies operated their own broadcasting stations and they used them as With plenty of money in the bank from his manufacturing business, Crosleya curious, driven man whose employees alternately described him as aloof and one of the boyscould have afforded the $100 radio. The 1-As first users were AT&Ts WEAF in Western Electric 6-B transmitter. This stations swelled from 67 to nearly 400. it was exclusively utilized by Western Electric until 1953, continued Batteries on the floor birthday, its certain that many of the technologies developed for that mercury vapor rectifier tubes for the plate voltage, and the fourth panel was