First-Hand:Observations of the History Of Radio/Television Since the Close of World War II
Observations of the History Of Radio/Television Since the Close of World War II
Submitted by Jules Cohen
At the start of World War II, consulting engineers largely dropped civilian activity as personnel either entered the Services or took jobs with manufacturers of materiel needed to prosecute the war. In my own case, I had been working as an engineer at the Bonneville Power Administration in Portland, Oregon. But with the advent of World II, I volunteered and was commissioned as an Ensign in the Naval Service in May of 1942. My active service continued for three and one-half years, during which I was promoted to Senior Lieutenant. At war's end, I was offered and accepted a job as Senior Engineer in the office of Weldon and Carr, Consulting Engineers. I started work there in December, 1945.
There existed at the end of the war a pent-up demand for radio facilities in the AM radio band, then running from 550 to 1500 kilohertz, later extended from 530 to 1700 kilohertz. A problem immediately apparent was the degree of interference if each applicant was granted as proposed.
To seek at least a partial response to that problem, the FCC called a meeting of applicants, which concluded that, to the extent possible, directional antennas should be employed to provide protection to co-channel and adjacent channel stations while at the same time providing service to the principal community to be served and its adjacent area. Blocks of the spectrum were assigned to the consulting engineering firms specializing in broadcast facilities to devise practical directional antenna systems providing interference protection to as many co-channel and adjacent channel stations as feasible. The result was not only the acceptance by owners of broadcast channel assignments but also a boon for consulting engineers supplying personnel to design the antenna systems, adjust the antennas to achieve the desired patterns, and make the measurements necessary to demonstrate to the FCC that the desired pattern had been achieved. I was engaged in all these engineering procedures on behalf of multiple clients.
After the initial group of station applicants had been accommodated, new entities, believing that fortunes could be made, sought out consulting engineers to study the use of the spectrum and conclude where new stations could be built with practical directional antennas protecting existing users.
A few entrepreneurs sought facilities in the newly established FM band at 88 to 108 megahertz with the lower four megahertz reserved for noncommercial broadcasters. Soon, demand grew for use of FM, providing more work for consulting engineers to select channels and prepare the engineering portions of applications to the FCC for construction permits and licenses.
Although the first television stations were built and started broadcasting in the 1930s, and quite a few homes had receivers, the advent of World Was II stopped production of transmitters and receivers. Nor did the FCC accept applications for the construction of TV stations. However, by the end of the war the FCC had found that serious interference was occurring between stations that had been built prior to the war and a revision of standards was necessary. Accordingly, a freeze was announced on the filing of any new requests for television construction permits, during which the FCC developed new standards to better provide service to the American public.. The freeze was not lifted until 1952. As in the case of AM broadcasting, multiple applications were filed for television stations and many conflicts resulted.
The year 1952 was a milestone for me. With two partners, Ed Vandivere and Wilson Wearn (both of them now deceased), we split from Weldon and Carr and founded our own firm -Vandivere, Cohen and Wearn, Consulting Engineers.
We made no public announcement of the founding of our firm except to lawyers whose practices were largely in the service of broadcasters, including existing operators and applicants for new facilities. Gradually, the existence of our firm became known and a number of Weldon and Carr clients for whom we had worked sought us out for their engineering work. The lifting of the television freeze by the FCC in 1952 resulted in our acquiring a number of applicants for television construction permits. I provided testimony for clients involved in hearings to determine which of the applicants for the same channel should be granted.
In 1983, the Association of Maximum Service Television, Inc. (MSTV) was formed and I was selected as their engineering consultant. By that time, I had lost both partners. Vandivere had accepted employment elsewhere as a physicist, which was his primary interest. Wearn had accepted a pleading by a group of new television owners to be a top executive for a station in Greenville, South Carolina. Although he and I had a good relationship and harmoniously operated our growing consulting firm, Wearn had strong ties to Greenville where his mother lived. Furthermore, he and his wife preferred to raise their growing twin daughters in the South rather than Northern Virginia.
Under my direction, the firm of Jules Cohen and Associates grew to accommodate our growing clientele. Of the total employees, numbering 19, eight were engineers.
By 1973 the FCC recognized that advances in technology warranted a new look at the then current system of analog television. Accordingly, the FCC established the Advisory Committee for Advanced Television Service (ACATS). Although ACATS had an initial life term of two years, its life was repeatedly extended until laboratory and field testing were completed in 1994.
Broadcasters, with the cooperation of the CATV and the consumer electronics manufacturing industries established the Advanced Television Test Center (ATTC) for subjective and objective system laboratory testing by experts. Field testing was to be conducted under the supervision of a Task Force appointed by the Chairman of ACA TS. I was appointed to serve as the head of the Task Force. The final Technical Report by ACATS was completed in October of 1995.
Initially, 21 entities indicated an intention to submit proposals for pre-certification of advanced systems. However, by the time to proceed with selection, only five systems remained. Initially, four of the five were analog, but when General Instrument Corporation proposed a digital system, three of the other proponents also switched to digital. Testing began with the finding that no digital system stood out as a winner.
Fortunately, a lawyer, Richard Wiley, who had been involved in the process from the beginning, convinced the sponsors of digital systems (AT & T, David Sarnoff Research Center (RCA), General Instrument Corporation, Zenith Electronics Corp., Thomson Consumer Electronics, North American Philips Corp. and MIT) to get together and devise a digital system better than any system so far proposed. That was done, resulting in the system that was ultimately tested in laboratories and the field. The consortium of manufacturers became known as the Grand Alliance.
Field testing benefited from the fortuitous move of the Charlotte, North Carolina Public Broadcasting system, making available to the field testing Task Force a tower and building for the housing of transmitters. Antennas for analog and digital VHF and digital UHF transmission were mounted on the tower with transmission lines running to appropriate transmitters in the building. Extensive field measurements of the newly proposed digital system showed that the digital system could provide service to equal or greater distance than can be provided by the Grade B contour of the analog system in use. The new digital system, with its improved picture quality, was adopted by the FCC as the standard for broadcast transmissions. As Chairman of the Field Testing Task Force, I was involved in the entire testing process, although we were fortunate to have Edmund Williams working with us, remaining full time in Charlotte supervising the field testing process.
An interesting series of events occurred in New York City. The New York/New Jersey Port Authority proposed to construct two buildings to be known as the World Trade Center (WTC), in Lower Manhattan. Normally, the Port Authority needed no permit from New York City for any proposed construction. However, in this case, building of the WTC required the closing of a street. This provided the New York City an excuse to hold a hearing. The hearing gave the New York television stations an opportunity to protest. Television was being transmitted from the Empire State Building. The twin towers of the proposed WTC would both cause reflections affecting reception in northern New York City and Westchester County, and block reception in a part of Staten Island.
The broadcaster's objection meant that the City might not grant a permit to build the WTC. Observations of the History Of Radio/Television Since the Close of World War II
To avoid that possibility, the Port Authority offered to strengthen the upper floors of the WTC, construct a 350-foot tower on the North Tower, relocate the television station and FM station antennas, and pay the Empire State Building the cost of the remaining months of the television and FM station leases. The broadcast stations accepted the offer and the building permit was granted.
When the north tower of the WTC was at full height, although the skin was still below the top, and the south tower was only at half height, the Port Authority announced that it was going to cancel the contract with the broadcasters because the claimed adverse effects of the WTC were not occurring. My firm was hired by the broadcasters to, if possible, counter the Port Authority's claims. We had a field car with mast extendible to 30 feet and equipped with a television set and oscilloscope.
We found that in the direction to the north, reflections were occurring but not of the magnitude ultimately expected when WTC construction was complete. We could identify, on the oscilloscope, the blip from the WTC by noting the distance along the oscilloscope trace and the known distance from the WTC. I prepared a report and, with broadcaster representatives, presented that report to the Port Authority representatives present in a meeting. Upon reviewing the report, no rebuttal was offered and the contract with the broadcasters no longer challenged.
Broadcasting from the WTC continued for many years until the tragic destruction of both towers on September 11, 2001.
Although the digital system authorized by the FCC was characterized as a high definition system, it was recognized that improvement was feasible. That improvement would require a new receiver but would be compatible with existing receivers. A committee was formed under my chairmanship and, as evidenced in the receivers currently available, the objective of better picture quality was achieved.
Unfortunately, I no longer have any files relative to the development of the improved HD and cannot add anything to the history of its achievement.