Ultra-Short Wave Radio Link across Bristol Channel

Abstract

ONE of the results of the study of the mode of propagation of ultra-short electric waves has been to show that for wave-lengths of from one to about nine metres, the effective range is limited to the horizon or the optical distance for ordinary vision. While this property prevents the application of such waves for long distance radio communication, it has for some time been recognised that this range of wave-lengths would be very suitable for providing a radio link in the ordinary telephone system. This application is of particular advantage in spanning short stretches of water, such as a channel or river estuary, where the present alternative is a submarine cable or a land-line following a circuitous route. According to recent reports in the Times and the Wireless World, tho Post Office Engineering Department has been investigating the possibilities of this application for some time past, and experiments have now successfully terminated in the setting-up of a radio link across the Bristol Channel. This link, which is twelve miles long, connects up the ordinary telephone land-lines at Lavernock, near Cardiff, on one side, with those at Hutton, near Weston-super-Maro, on the other. The wave-length employed is about five metres, and the transmitters and receivers are placed in separate huts at each site. The aerial system consists of horizontal dipoles connected to the terminal apparatus by special transmission lines, and the whole equipment has been designed to work unattended, apart from periodic maintenance operations.