The design and use of radio-frequency open-wire transmission lines and switchgear for broadcasting systems

The paper describes the various types of transmission lines in use at transmitting stations of the British Broadcasting Corporation, their impedance, attenuation and power-carrying characteristics, together with results of various tests, general details of construction, and methods of matching the load to the transmission line. The major part of the work described was carried out before the end of 1943. The paper is written primarily from the point of view of the engineer engaged on design and practical work in the field. Data are included enabling the most suitable transmission line for any practical purpose to be designed. The range of frequencies considered is from 0.2 to 25 Mc/s; of this range those up to 2 Mc/s are considered as medium waves and those from 2 Mc/s to 25 Mc/s as short waves.