RADIO COMMUNCATION.

Hawera Star, Volume XLV, 10 September 1925, Page 10

RADIO COMMUNCATION.

WITH OTHER PLANETS. EARTH FOR EVER BARRED. WASHINGTON. Aug. 22. The earth is- for ever barred from communicating bv radio with other planets, according to a discovery announced by the Navy Department ( which is a direct confirmation cf cat Heaviside theory). An impervious layer of eleetncally-c-.h urged molecules surrounds the earth atmosphere, like the skin of an orange, and through it wireless waves cannot pass. What the world loses by this discovery. in i'.s efforts to extend its knowledge of the universe, it gains, however, in increased efficiency in terrestrial wireless communication. The announcement, of the Secretary for the Nav.v, Mr. Curtis Wilbur, confirms the theory of an ionised region in the higher levels of the atmosphere, which is determined as constituting the ceiling of the sky. Additional research is required to determine its sizA shape, and location, but it- is said to lie more, than a hundred miles from the earth. This ceiling, or ionised layer, acts as a-deflecting surface to the electric waves, under which waves are 'guided round the- world.

These discoveries, made by the IT.S. Naval Research Laboratory, co-operat-ing with the Carnegie Institute, are expected lo improve radio and- wireless communications by eliminating “fading.” Tt is also stated that, under this now system, a high frequency transmitting station could be- built for £12,000, instead of. ns at present, the stations costing £500.000.

Air. Wilbur described the ionised Inver as flic plane of maximum density, its varying height above the surface of the earth depending upon the ceaseless billowing of the atmospheric envelope that surrounds the globe. The maximum height, probably was inside 300 miles. When a radio wave is dispatched from a station it shoots skyward until it hits this layer, whence; it rebounds to the earth or travels along the earth like sound waves under a vault or dome. Scientists experimenting with short wave-length radio transmission •have been baffled by the peculiar behaviour of these waves. Signals could be heard at a distance of forty or fifty miles, and then would disappear, and could not. be heard again until points 100 or perhaps lOflO miles distant, picked) them np. These intervals of silence became known as “skip distance. ” Experiments now indicate that two waves exist. One runs along the earth and the other along the dense upper layer. It is this second (upper) wave that carries the long distance.