2015_04_05_ewr-sfo_318 : 無料・フリー素材/写真
2015_04_05_ewr-sfo_318 / Nfrastructure
| ライセンス | クリエイティブ・コモンズ 表示 2.1 |
|---|---|
| 説明 | Photos of the KNBR/680 transmitter site, on a salt swamp alongside San Francisco Bay, in Redwood Shores, California. KNBR is one of the original "clear channel" stations in the U.S., meaning the alpha occupant of its channel. When I was a kid I could get KNBR at my home in New Jersey on some nights,The station's transmitting system is somewhat unusual, with a "sectionalized" 550-foot tower with the two sections fed separately, giving the signal extra punch, with two antennas working in parallel to push the signal outward toward the horizon. The upper section of the tower also features a "capacitive hat" increasing the electrical length of the radiator.KNBR started as KPO in 1922 and was KNBC for awhile.This tower was built in 1949, and replaced a flat-top "T" or "clothesline" antenna suspended between two towers. (See here.) One of those towers still stands as a backup antenna. The base of the other is still visible. The four red "HAZ" signs on the ground tell airplanes there is a HAZard in the middle.Also at this site are the tower bases for shortwave station KGEI, which operated here until 1994. |
| 撮影日 | 2015-04-05 12:30:36 |
| 撮影者 | Nfrastructure |
| タグ | |
| 撮影地 | |
| カメラ | Canon EOS 5D , Canon |
| 露出 | 0.002 sec (1/500) |
| 開放F値 | f/6.3 |
| 焦点距離 | 105 mm |