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Summary
| Description |
Antenna location at the U.S. Naval Communication Station Harold E. Holt in Exmouth, Western Australia, in 1972. This is a very low frequency (VLF) transmitter which communicates with submerged submarines. This type of antenna is called a "Trideco" or umbrella antenna. It consists of multiple steel masts which radiate radio waves, with a network of cables attached to their tops. The cables do not themselves radiate radio waves, but serve as a capacitive top-load, adding capacitance to the top of the antenna to make it more efficient. On the ground under the antenna there is an elaborate ground system called a counterpoise consisting of radial cables in a star shape suspended a few feet above the ground. |
| Date | |
| Source | NAVELEX 0101, 113 Fig. 3-14 |
| Author | US Navy, Naval Electronics Systems Command |
Licensing
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This file is a work of a sailor or employee of the U.S. Navy, taken or made as part of that person's official duties. As a work of the U.S. federal government, it is in the public domain in the United States.
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| This file has been identified as being free of known restrictions under copyright law, including all related and neighboring rights. | ||
Original upload log
The original description page was here. All following user names refer to en.wikipedia.
| Date/Time | Dimensions | User | Comment |
|---|---|---|---|
| 2011-04-01 17:26 | 1379×954× (320560 bytes) | Mcg410 | {{Information |Description = Diagram of Antennas at NCS Harold E Holt |Source = NAVELEX 0101, 113 Fig. 3-14 |Date = 1972 |Author = US Navy, Naval Electronics Systems Command |Permission = |other_versions = }} |
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| Date/Time | Thumbnail | Dimensions | User | Comment | |
|---|---|---|---|---|---|
| current | 15:18, 15 November 2014 | | 1,379 × 954 (313 KB) | Cobatfor | == {{int:filedesc}} == {{Information |Description={{en|Antenna location at the U.S. Naval Communication Station Harold E. Holt in Exmouth, Western Australia, in 1972.}} |Source=Transferred from [http://en.wikipedia.org en.wikipedia]<br/> (Original text... |
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