Sterba antenna

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Before the HRS antenna became the default design for high power broadcasting in the 1950s, Sterba curtains were used.

Sterba curtains are modest-gain single-band curtain array antennas. They are named after Ernest J. Sterba, who developed a simple shortwave curtain array for Bell Labs in the 1930s. [1] Sterba curtain arrays are described in William Orr's Radio Handbook.

Curtain array

Curtain arrays are a class of large multielement directional wire radio transmitting antennas, used in the shortwave radio bands. They are a type of reflective array antenna, consisting of multiple wire dipole antennas, suspended in a vertical plane, often in front of a "curtain" reflector made of a flat vertical screen of many long parallel wires. These are suspended by support wires strung between pairs of tall steel towers, up to 300 ft (90 m) high. They are used for long-distance skywave transmission; they transmit a beam of radio waves at a shallow angle into the sky just above the horizon, which is reflected by the ionosphere back to Earth beyond the horizon. Curtain antennas are mostly used by international short wave radio stations to broadcast to large areas at transcontinental distances.

William (Bill) Ittner Orr (1919–2001) was an engineer, educator, and communicator. He was the American author of numerous amateur radio and radio engineering texts. He is best known as the author of The W6SAI Antenna Handbook and fondly remembered for the 1959 Radio Handbook.

There are multiple feed arrangements for the Sterba curtain arrays, as with HRS type antennas. However, Sterba arrays provide a very limited gain-bandwidth system for the demands of modern shortwave broadcasting systems.

Sterba curtain arrays preceded HRS type antennas by less than a decade. Only about 1% of high power HF broadcasting antennas in use in the 2000s are Sterba type curtain arrays. It is expected that by 2020 that all Sterba type curtain arrays will have been decommissioned.

Amateur Radio operators do still build Sterba curtain arrays. [2] It can be argued that since amateur radio transmissions only take place in narrow bands, then a Sterba array remains a decent solution for their needs.

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Medium wave

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Ultra high frequency radio waves

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Medium frequency Frequencies between 300 kHz to 3 MHz

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High frequency frequencies between 3-30MHz

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T2FD antenna

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ALLISS

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Shortwave relay station

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References

  1. "Archived copy" (PDF). Archived from the original (PDF) on 2012-01-27. Retrieved 2012-02-28.
  2. http://www.hamuniverse.com/sturba.html