Spectacular Radio Telephony Experiment

Radio Record, Volume VI, Issue 2, 22 July 1932, Page 2

Spectacular Radio Telephony Experiment

Between Aeroplane and Train Somme AN experiment to test the poss{bility of wireless telephonic communication between passengers' in trains and aircraft was carried out successfully in England recently. Messages . were sent and received between the north-ward-bound "Flying Scotsman" and the Imperial Airways liner Heracles, which was flying to Glasgow. At the rear of the Flying Scotsrian was attached a standard Hast Coast brake-van which had been equipped as a wireless receiving and transmitting station with the call signal GSFL. For the experiment a Marconi set, of the standard type used in aircraft, working on a wavelength of 820 metres, was installed. The Heracles took off from Croydon at 11 a.m-an hour after the "Flying Scotsman" left King’s Cross-and overtook the train, which was identifiable by its name painted on its roof, shortly before reaching Grdntham. Wireless communication wis promptly established, and with the aid of both a loudspeaker and headphones those in the train were ablé to call and converse with acquaintances in the aircraft while travelling at full speed. In spite of some interference of aircraft and . locomotive noises, reception was sur: prisingly clear. After flying with the train for some 40 miles, the Heracles left it at Retford. Communication was; however, maintained for as long as possible, until it grew too faint with increasing distance. Owing to the exigencies of time, the train had been equipped for the test with a short inside aerial, which limited the distance over which transmission could be effected. Even so, the results obtained were better than had been anticipated. The train proved capable of transmitting messages up to a distance of nearly five miles, and for some time after that it was considered that further .communication would be impossible. Reaéption from the aircraft continued longer, and was still good’ when the ~ Herdcles switched over to its normal of. 900 metres. With more powerful apparatus and a suitable aerial it is believed that wireless telephonic communication between trains and aircraft could be satisfactorily carried on at distances up to 50 miles. =