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Goliath transmitter was a very low frequency (VLF) transmitter for communicating with submarines, built by Nazi Germany's Kriegsmarine navy near Kalbe an der Milde in Saxony-Anhalt, Germany, which was in service from 1943 to 1945.
A gin pole used to install a weather vane atop the 200-foot steeple of a church Roof trusses being assembled with gin poles. The gin pole is derived from a gyn, and considered a form of derrick, called a standing derrick or pole derrick, [2] distinguished from sheers (or shear legs) by having a single boom rather than a two-legged one.
A sailboat's mast is supported by shrouds (side-to-side) and stays (fore-and-aft) – nautical equivalents of guy wires.. A guy-wire, guy-line, guy-rope, down guy, or stay, also called simply a guy, is a tensioned cable designed to add stability to a freestanding structure.
Guyed masts are frequently used for radio masts and towers. The mast can either support radio antennas (for VHF, UHF and other microwave bands) mounted at its top, or the entire structure itself can function as a mast radiator antenna (for VLF, LF, MF). In the latter case, the mast needs to be insulated from the ground. Guyed radio masts are ...
The antenna used for broadcasting through the 1920s was the T-antenna, which consisted of two masts with loading wires on top, strung between them, requiring twice the construction costs and land area of a single mast. [2] (pp 77–78) In 1924 Stuart Ballantine published two historic papers which led to the development of the single mast antenna.
If the mast has a long, thin cross-section and makes up a significant area of the airfoil, it is called a wing-mast; boats using these have a smaller sail area to compensate for the larger mast area. There are many manufacturers of modern masts for sailing yachts of all sizes, a few notable companies are Hall Spars, Offshore Spars, and Southern ...
The antenna must be very large at the VLF frequencies used; the supporting masts are 250–300 metres (820–980 ft) high, and the topload is about 1,900 metres (6,200 ft) in diameter. The trideco antenna was developed for high power naval transmitters, which transmit on frequencies between 15 and 30 kHz at powers up to 2 megawatts, to ...
[9] [better source needed] A length of at least 20 metres (66 ft) of 75 Ω (50 Ω) cable is recommended for operation without a balun. [10] [11] A transmatch (antenna tuner) is not required to use this antenna near its nominal design frequency of 14 MHz, and judicious length adjustments can sometimes include one other frequency band. All other ...
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