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Broadband shortwave base antennas traditionally fall into two main categories: Resistively loaded antennas which can be inexpensive and reasonably compact but inefficient at lower frequencies. Large elaborate and very expensive, non-loaded designs. (These can cost upward of $80,000 to purchase and install).
The antenna elements for the lowest frequency band are located at the exterior of the antenna. When constructing multi-band hexbeams, the vertical spacing of each element is critical, because the elements of a multi-band hexbeam mutually influence each other and if the elements are not parallel, parameters of the antenna may change undesirably.
WMLK (9.275, 17.525 & 15.15 MHz), is a shortwave radio prominent outreach tool of the Assemblies of Yahweh, based in Bethel, Pennsylvania.The station’s call sign, "WMLK," reflects the Hebrew word (MLK) "malak" (מַלְאָךְ), meaning “messenger” or “angel,” symbolizing its mission as a messenger of Yahweh’s truth to the world. [1]
The log-periodic is commonly used as a transmitting antenna in high power shortwave broadcasting [15] stations because its broad bandwidth allows a single antenna to transmit on frequencies in multiple bands. The log-periodic zig-zag design with up to 16 sections has been used.
Ultimately shortwave relays for network programming was determined to be inferior to dedicated telephone line connections, and the transmissions to KFKX ended, with the Hastings operation closing on June 1, 1927. [6] In 1922, a 1 kW shortwave transmitter was installed at Westinghouse's factory in East Pittsburgh, Pennsylvania, with call sign ...
Antennas can be classified in various ways, and various writers organize the different aspects of antennas with different priorities, depending on whether their text is most focused on specific frequency bands; or antenna size, construction, and placement feasibility; or explicating principles of radio theory and engineering that underlie ...
Before the HRS antenna became the default design for high power broadcasting in the 1950s, Sterba curtains were used to transmit shortwave broadcasts. 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]
ALLISS allows a broadcaster to change the following shortwave transmission parameters at any time: direction (azimuths from 0 to 360 degrees, rate: ~1 deg / 6 sec), broadcast frequency, and antenna configuration (i.e.: HR 4/4/1 -> HR 6/4/1). All of these transmission mode changes can take effect in as little as 5 minutes.