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084f2db8c6 Earth's surface (ground or water) then diffusely reflects the incoming wave back towards the ionosphere. The ionosphere is a region of the upper atmosphere, from about 80km to 1000km in altitude, where neutral air is ionized by solar photons and cosmic rays. For the satellite terminal company in Ottawa, see SkyWave Mobile Communications. Data Communications Training. Further reading. On 19 October amateurs in New Zealand and England completed a 90-minute two-way contact nearly halfway around the world.
Bureau of Navigation, Department of Commerce. By 1924 many additional specially licensed amateurs were routinely making transoceanic contacts at distances of 6000 miles (9600km) and more. Frequencies lower than 3kHz have a wavelength longer than the distance between the Earth and the ionosphere. On October 10, the Third National Radio Conference made three shortwave bands available to U.S. Far more spectrum is available for long distance communication in the shortwave bands than in the long wave bands; and shortwave transmitters, receivers and antennas were orders of magnitude less expensive than the multi-hundred kilowatt transmitters and monstrous antennas needed for long wave. Chapter 16, #38, Analysis of RDF Bearings. Ionospheric Radio. in 1934. If the ionization is not great enough, the scatter wave is initially deflected downwards, and subsequently upwards (above the layer peak) such that it exits the top of the layer slightly displaced. ^ K.Rawer:Wave Propagation in the Ionosphere.