2011_03_14-15_aus-iah-fra-zch_014 : 無料・フリー素材/写真
2011_03_14-15_aus-iah-fra-zch_014 / Nfrastructure
| ライセンス | クリエイティブ・コモンズ 表示 2.1 |
|---|---|
| 説明 | The KLBJ transmitter east of Austin, Texas, on State Farm to Market Road 973, just west of Highway 130, northeast of Austin Bergstrom International Airport, overlooking the Colorado River. This is one in a series of shots taken after departing from the airport on a flight to Houston. The land around the transmitter appears to be heavily excavated, presumably by the concrete plant next door. KLBJ uses only one tower by day, with 5000 watts, and all four towers by night, with 1000 watts. The towers are a little under 400 feet high, and surrounded by ground systems of buried conductors (usually copper straps, in sites like this). The night pattern can be seen here. Here's a daytime coverage map, showing the signal's fringes reaching from Oklahoma to Mexico. The ground conductivity in the area is exceptionally high, which is why a signal this weak can reach so far. A low position on the AM dial also helps, since longer waves on AM travel better along the ground. |
| 撮影日 | 2011-03-14 17:43:26 |
| 撮影者 | Nfrastructure |
| タグ | |
| 撮影地 | |
| カメラ | Canon EOS 5D , Canon |
| 露出 | 0.008 sec (1/125) |
| 開放F値 | f/7.1 |
| 焦点距離 | 50 mm |