Stratovision

Last updated
Westinghouse and Glenn L. Martin employees pose with B-29 Superfortress used in Stratovision tests. In rear row from left are Frank Gordon Mullins and C.E. Nobles, head of Stratovision for Westinghouse. Stratovision.jpg
Westinghouse and Glenn L. Martin employees pose with B-29 Superfortress used in Stratovision tests. In rear row from left are Frank Gordon Mullins and C.E. Nobles, head of Stratovision for Westinghouse.

Stratovision was an airborne television transmission relay system using aircraft flying at high altitudes. In 1945 the Glenn L. Martin Company and Westinghouse Electric Corporation originally proposed television coverage of small towns and rural areas, as well as the large metropolitan centers, by fourteen aircraft that would provide coverage for approximately 78% of the people in the United States. Although this was never implemented, the system has been used for domestic broadcasting in the United States, and by the U.S. military in South Vietnam and other countries.

Contents

Technology

Because the broadcasting antenna for Stratovision is usually hung beneath the aircraft in flight, it naturally has a great command of line-of-sight propagation. Although transmission distances are dependent upon atmospheric conditions, a transmitting antenna 30,000 feet (9.1 km) above the Earth's surface has a line of sight distance of approximately 211 mi (340 km).

A Stratovision 25 kW transmitter operating from 30,000 feet (9.1 km) at 600 MHz will achieve a field intensity of 2 millivolts per meter for a 30-foot (9.1 m) high receiving antenna up to 238 miles (383 km) away from the aircraft.

Early tests

Stratovision tests were undertaken between June 1948 to February 1949. The first phase was undertaken by the Glenn L. Martin Co. and Westinghouse using a twin-engine PV-2 aircraft flying at 25,000 feet (7.6 km) that transmitted with 250 watts on 107.5 MHz and 5 kW on 514 MHz at Baltimore, Maryland so that recordings could be made at various locations ranging from Norfolk, Virginia to Pittsburgh, Pennsylvania and Boston, Massachusetts.

The second phase of testing was undertaken by these companies using a stripped-down B-29 Superfortress flying at 30,000 feet (9.1 km). The plane was equipped to receive a relay transmission from WMAR-TV in Baltimore, which was then relayed over a 5 kW video transmitter and a 1 kW audio transmitter for reception on 82-88 MHz with a television set tuned to Channel 6.

The aircraft received its originating signals from circular dipoles attached to a streamlined eight-foot (2.5 m) mast atop of the aircraft's vertical tail fin. The retractable 28 feet (8.5 m) long broadcasting antenna hung vertically beneath the aircraft. It was composed of a two-element turnstile array for video and a single-element circular dipole for sound transmissions.

The receivers, transmitters and necessary air-conditioning were all powered by the plane's engines using three 15 kVA, 500 Hz alternators. Without air conditioning the transmitters in the interior of the aircraft would have generated a temperature of 134 degrees Fahrenheit (57 degrees Celsius) with an outside air temperature of 25 degrees Fahrenheit (minus 4 degrees Celsius).

On 23 June 1948 the system's airborne transmitter rebroadcast the Republican National Convention, being held in Philadelphia, Pennsylvania, to the surrounding nine-state area during the 9 to 10 pm EDT time period. As part of the activity, a receiver was set up in a hall in Zanesville, Ohio, a small city on the outskirts of the broadcast area, to demonstrate to invited newspaper reporters that the system was capable of reaching "small town and farm homes". [1]

The tests were watched by many television viewers who sent in reception reports. From these reports it was calculated that Stratovision would require only eight relay planes to provide a transcontinental network, and six additional planes to provide coverage to 78% of the United States. Charles Edward Nobles, the head of Stratovision for Westinghouse, said in his report:

"The major technical problems of the system have been solved, and the commercial development awaits only the crystallization of public demand for the expanded services offered by airborne broadcasting, application of the system by the radio industry to meet this demand, and the clarification of channel facilities available to make possible this application."

Sports

On September 30, 1954, Cuba used a DC-3 to broadcast a baseball championship game from the United States, the first live extracontinental broadcast. [2]

Education

In 1961 a nonprofit organization, Midwest Program on Airborne Television Instruction, commenced a Stratovision service from the airfield of Purdue University. The effort began as a three-year experiment funded by the Ford Foundation. The program organized, produced and transmitted educational television programs four days a week from a DC-6AB aircraft flying at 23,000 feet (7,000 m) over the community of Montpelier in north central Indiana.

MPATI delivered its programs to television channels 72 (call sign KS2XGA) and 76 (KS2XGD) in the UHF band, by transmitting videotaped lectures from the aircraft to an estimated potential 5,000,000 students in 13,000 schools and colleges. The aircraft were equipped with two 2-inch (51 mm) videotape machines and two UHF transmitters.

When MPATI signed on it used an "Indian head" test pattern card which was shown for five minutes before and between programs. The service ended in 1968 when it became embroiled in legal action over their application of Stratovision in a controversy with the Westinghouse company.

Propaganda

Vietnam War

During the Vietnam War, the United States Navy used Stratovision television technology when it flew Operation Blue Eagle from 1966 to 1972 over the Saigon area of South Vietnam. The television programs were aimed at two audiences on two channels: one was aimed at the general public and the other was intended for the information and entertainment of US troops who were stationed in South Vietnam.

On January 3, 1966, a Broadcasting magazine article, "Vietnam to get airborne TV: Two-channel service —one for Vietnamese, other for U.S. servicemen—starts this month", noted:

Television broadcasting in South Vietnam ... begins January 21 and it's going to be done from the air. Two airplanes, circling 10,000 to 20,000 feet [3.0 to 6.1 kilometres] above the ground, will broadcast on two TV channels—one transmitting Saigon government programs; the other U.S. programs. The project is being handled by the U.S. Navy. Also involved are the U.S. Information Agency and the Agency for International Development. Work on modifying two Lockheed Super Constellations has been underway by Navy electronics experts at Andrews Air Force Base ... The project is an outgrowth of a broadcasting plane used by the Navy during the Cuban and Dominican Republic crises when both radio and television were beamed to home in those countries.

The same article went on to report that during the Baseball World Series of October 1965 Stratovision had also been used to bring the games to the troops. The aircraft had picked up Voice of America radio broadcasts from California and relayed the signal to a ground broadcasting station. The Agency for International Development (AID) had purchased through the military Post Exchange Service, 1,000 monochrome, 23-inch television sets modified to operate on a variety of domestic power sources, and which had been airlifted to South Vietnam on December 28, 1965. They were to be put into community facilities around Saigon. AID was also spending $2.4 million to supply a total of 2,500 TV sets to South Vietnam.

The entire project was under the control of Captain George C. Dixon, USN. He claimed to be installing AM, FM, shortwave and TV transmitters on the aircraft which would get their power from an onboard 100 kW diesel-fueled generator. The planes would not only relay programs from film chain kinescopes and video recorders, but they would also have live cameras to create their own live programs.

Ground transmissions would be received from the aircraft on TV sets tuned to channel 11 for Armed Forces Television, and channel 9 for programs in Vietnamese. On radio the broadcasts would be tuned to 1000 kHz for AM and 99.9 MHz for FM.

On 7 February 1966, Broadcasting magazine reported that after working out a number of technical problems that the first show on channel 9 would begin at 7:30 p.m. and feature South Vietnamese Prime Minister Nguyen Cao Ky and U.S. Ambassador Henry Cabot Lodge in a videotaped production, followed by channel 11 at 8 p.m. with General Westmoreland introducing a two-hour program which incorporated one hour of the Grand Ole Opry filmed in Nashville, Tennessee. After that the Vietnamese channel would be seen for one and half hours a day and the U.S. channel for three hours daily.

On 8 February 1966 The New York Times article "South Vietnamese Watch First TV Show" reported that South Vietnamese viewers had to strain their ears because the speakers on the TV sets would need to be amplified if they were going to be heard by a room full of people watching THVN-TV channel 9. The U.S. programming on NWB-TV channel 11 was Bob Hope in a two-hour special called Hollywood Salute to Vietnam, followed by half-an-hour of the Grand Ole Opry and another half-hour of the quiz show I've Got a Secret . The regular line-up of shows included Bonanza , Perry Mason , The Ed Sullivan Show , and The Tonight Show Starring Johnny Carson .

1999 NATO bombing of the Federal Republic of Yugoslavia

EC-130 Commando Solo was used in propaganda warfare during the 1999 NATO bombing of the Federal Republic of Yugoslavia with questionable success. Production was very cheap, below local TV standards in Federal Republic of Yugoslavia with slide show and narration based news. Quality of reception was very poor and area of coverage was rather small.

Iraq War

During the 2000s, the EC-130 Commando Solo has been used to broadcast information and propaganda for the United States over a variety of television and radio frequencies. It has been used in several areas of operation, including Bosnia and Iraq.

Pirate television

In 1969, news stories began to appear in the United Kingdom that Ronan O'Rahilly, the founder of the pirate radio ship based service called Radio Caroline, which at that time was not on the air, was about to launch Caroline Television instead. [3] His plans called for two aircraft, one in service and one as a relief, which would transmit commercial television programs to Britain by Stratovision. Although these stories continued for some time, nothing became of the project. To date[ when? ] no pirate radio or television service has ever operated by means of Stratovision.

Use as a temporary service

The advent of fibre optic cable television systems and direct broadcast satellite services has supplanted Stratovision as a permanent means of television delivery. The Stratovision concept continues to be used as a stop-gap measure where land-based transmitters are not possible and where large areas of territory need to be served with a television program.

Related Research Articles

<span class="mw-page-title-main">Very high frequency</span> Electromagnetic wave range of 30-300 MHz

Very high frequency (VHF) is the ITU designation for the range of radio frequency electromagnetic waves from 30 to 300 megahertz (MHz), with corresponding wavelengths of ten meters to one meter. Frequencies immediately below VHF are denoted high frequency (HF), and the next higher frequencies are known as ultra high frequency (UHF).

International broadcasting consists of radio and television transmissions that purposefully cross international boundaries, often with then intent of either allowing expatriates to remain in touch with their countries of origin as well as educate, inform, and influence residents of foreign countries. Content can range from overt propaganda and counterpropaganda to cultural content to news reports that reflect the point of view and concerns of the originating country or that seek to provide alternative information to that otherwise available. In the first half of the twentieth century, international broadcasting was used by colonial empires as a means of connectong colonies with the metropole. When operated by governments or entities close to a government, international broadcasting can be a form of soft power. Less frequently, international broadcasting has been undertaken for commercial purposes by private broadcasters.

<span class="mw-page-title-main">Crystal Palace transmitting station</span> Telecommunications site in Bromley, England

The Crystal Palace transmitting station, officially known as Arqiva Crystal Palace, is a broadcasting and telecommunications site in the Crystal Palace area of the London Borough of Bromley, England. It is located on the site of the former television station and transmitter operated by John Logie Baird from 1933.

The Sutton Coldfield transmitting station is a broadcasting and telecommunications facility located in Sutton Coldfield, Birmingham, England. In terms of population covered, it is the third most important transmitter in the UK, after Crystal Palace in London and Winter Hill near Bolton.

Shortwave broadcasting in the United States allows private ownership of commercial and non-commercial shortwave stations that are not relays of existing AM/MW or FM radio stations, as are common in Africa, Europe, Asia, Oceania except Australia and Latin America. In addition to private broadcasters, the United States also has government broadcasters and relay stations for international public broadcasters. Most privately owned shortwave stations have been religious broadcasters, either wholly owned and programmed by Roman Catholic and evangelical Protestant charities or offering brokered programming consisting primarily of religious broadcasters. To better reach other continents of the world, several stations are located in far-flung US territories. Shortwave stations in the US are not permitted to operate exclusively for a domestic audience; they are subject to antenna and power requirements to reach an international audience.

<span class="mw-page-title-main">Winter Hill transmitting station</span> Telecommunications site in Lancashire, UK

The Winter Hill transmitting station is a broadcasting and telecommunications site on Winter Hill, at the south eastern boundary of the Borough of Chorley, Lancashire, England, and above Bolton. It is owned and operated by Arqiva.

<span class="mw-page-title-main">Wenvoe transmitting station</span> Transmission station in Wales

The Wenvoe transmitting station, officially known as Arqiva Wenvoe, is the main facility for broadcasting and telecommunications for South Wales and the West Country. It is situated close to the village of Wenvoe in the Vale of Glamorgan, Wales, in the UK.

<span class="mw-page-title-main">Microwave transmission</span> Transmission of information via microwaves

Microwave transmission is the transmission of information by electromagnetic waves with wavelengths in the microwave frequency range of 300 MHz to 300 GHz of the electromagnetic spectrum. Microwave signals are normally limited to the line of sight, so long-distance transmission using these signals requires a series of repeaters forming a microwave relay network. It is possible to use microwave signals in over-the-horizon communications using tropospheric scatter, but such systems are expensive and generally used only in specialist roles.

<span class="mw-page-title-main">Television and mass media in Vietnam</span>

Television in Vietnam began to appear in the mid-1960s in Saigon, with the appearance of Saigon Television Station. In 1970, in the North, Voice of Vietnam broadcast the first test television program. In the late 1970s, color television was introduced and broadcast experimentally. Today, television in Vietnam is available in many modes of broadcasting, with many national and local channels, broadcast or pay with more than 200 channels available to viewers. Vietnam completed the digital television transitions on December 28, 2020.

<span class="mw-page-title-main">Voice of Vietnam</span> National broadcasting service of Vietnam

The Voice of Vietnam is the Vietnamese national radio broadcaster. Directly run by the government of Vietnam, it is tasked promote the policies of the Party and the laws of the state.

<span class="mw-page-title-main">DZBB-TV</span> Television station in Metro Manila, Philippines

DZBB-TV is a television station in Metro Manila, Philippines, serving as the flagship of the GMA network. It is owned and operated by the network's namesake corporate parent alongside GTV flagship DWDB-TV. Both stations share studios at the GMA Network Center, EDSA corner Timog Avenue, Diliman, Quezon City, while DZBB-TV's hybrid analog and digital transmitting facilities are located at the GMA Tower of Power, Tandang Sora Avenue, Barangay Culiat, Quezon City and Digital SFN relay towers located at PBCom Tower in Makati City, Zen Towers in Manila, Antipolo City, and Angeles City, Pampanga.

The Oxford transmitting station is a broadcasting and telecommunications facility, situated on land 129.5 metres (425 ft) above Ordnance Datum to the north east of the city of Oxford, in Oxfordshire, England. It has a guyed steel lattice mast which is 154.4 metres (507 ft) in height to the top of the main steel structure. The UHF television antenna, which consist of a vertical array of transmitting panels, is mounted above the steel structure. The total height of the mast to the top of this UHF antenna is 165.7 metres (544 ft). It is owned and operated by Arqiva.

<span class="mw-page-title-main">Haverfordwest transmitting station</span> Broadcasting and telecommunications facility

The Haverfordwest transmitting station is a broadcasting and telecommunications facility located at Woodstock about 13 km (8 mi) to the north east of the town of Haverfordwest, in Pembrokeshire, Wales. It was originally built by the BBC, entering service in early 1964 acting as a main transmitter for the 405-line VHF television system, and as a repeater for Band 2 VHF FM radio received off-air from Blaenplwyf transmitting station. It is now owned and operated by Arqiva.

The Midwest Program on Airborne Television Instruction (MPATI) was a special broadcasting initiative designed to broadcast educational television programming to schools, especially in areas where local educational television stations are either difficult to receive or unavailable. From 1961 through 1968, MPATI's programming broadcast from two DC-6AB aircraft based at the Purdue University Airport in West Lafayette, Indiana, using a broadcasting technique known as Stratovision.

<span class="mw-page-title-main">Broadcast relay station</span> Repeater transmitter

A broadcast relay station, also known as a satellite station, relay transmitter, broadcast translator (U.S.), re-broadcaster (Canada), repeater or complementary station (Mexico), is a broadcast transmitter which repeats the signal of a radio or television station to an area not covered by the originating station.

<span class="mw-page-title-main">Radio</span> Use of radio waves to carry information

Radio is the technology of communicating using radio waves. Radio waves are electromagnetic waves of frequency between 3 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmitter connected to an antenna which radiates the waves. They are received by another antenna connected to a radio receiver. In addition to communication, radio is used for radar, radio navigation, remote control, remote sensing, and other applications.

<span class="mw-page-title-main">CKCX</span> Former CBC shortwave radio station near Sackville, New Brunswick, Canada

CKCX was the call sign used for the Canadian Broadcasting Corporation's shortwave transmitter complex near Sackville, New Brunswick at the Tantramar Marshes. The Sackville Relay Station was operated by Radio Canada International and broadcast its programming around the world as well as relay transmissions from several foreign shortwave broadcasters. Domestically, it transmitted broadcasts on 9.625 MHz to northern Quebec by CBC North, the James Bay Cree Communications Society and Taqramiut Nipingat, the Inuit communications society of the Nunavik region of northern Quebec. The CKCX designation was assigned after CBC Radio's CBA, under whose licence the Sackville complex originally operated, moved to Moncton in 1968. Sackville was also used by Radio Japan, China Radio International, Voice of Vietnam, BBC World Service, Deutsche Welle and Radio Korea as part of a transmitter time exchange agreement.

<span class="mw-page-title-main">Millennium Transmitter</span> Communications tower in Quezon City, Philippines

The Millennium Transmitter is a 720 ft (219.5 m) tall mast owned by ABS-CBN Corporation and operated by Advanced Media Broadcasting System located at the ABS-CBN Broadcasting Center, Mother Ignacia Street corner Sgt. Esguerra Avenue, Barangay South Triangle, Quezon City. Since September 13, 2022, the transmitter is being used by AMBS to serve as the platform for television transmission of ALLTV on analog Channel 2 and digital Channel 16. It was also used as the main transmission site for ABS-CBN-owned DWAC-TV Channel 23, the flagship station of ABS-CBN Sports and Action, before shutting down in 2020 and its frequency reassigned to Aliw Broadcasting Corporation and its radio station DWRR until it was relocated to Antipolo when the transmitter was upgraded by the end of 1999.

<span class="mw-page-title-main">St Hilary transmitting station</span> Transmitting station in Wales

The St Hilary transmitting station is a facility for telecommunications situated close to the village of St Hilary, Glamorgan in the Vale of Glamorgan, Wales, in the United Kingdom. It comprises a 229-metre (750 ft) guyed mast with antennas attached at various heights. The site was established in 1958 for Independent Television transmission on VHF. Transmissions from the site include FM radio, DAB radio and mobile telephone signals.

W8XH was a Buffalo, New York radio station, authorized by the Federal Communications Commission (FCC) as an "experimental audio station", which was owned by the Buffalo Evening News, and which operated from 1934 to 1939. It was the first apex band station, i.e. the first to transmit programming intended for the general public over what was then known as "ultra-high short-wave" frequencies. W8XH primarily simulcast programming originating from a co-owned AM radio station, WBEN, but it also aired some original programs. It ceased broadcasting in July 1939, after the newspaper began to focus on operation of an experimental facsimile broadcasting station, W8XA, which in turn shut down shortly prior to World War II and was succeeded after the war by the establishment of an FM station.

References

  1. Air & Space magazine, Vol 22 No 3, August 2007, "Broadcast Bomber", p. 18
  2. Guido Sapienza "Il sistema televisivo cubano", p. 67
  3. Simons, Graham M. (2012). B-29 Superfortress: Giant Bomber of World War Two and Korea. Barnsley, England: Pen & Sword. ISBN   9781783376193.