Line repeating amplifiers for broadcasting purposes

Although methods for the electrical transmission of sound frequencies have been in existence for a long time, it is only in recent years that the transmission of high quality music and speech has received serious attention. When the power of radio transmitters was continually increased it became desirable to have the studios and transmitting stations a wide distance apart, since the transmitter was best situated outside a city, white the studio should most conveniently remain in a central position. Also, interconnection between one central studio and a number of transmitters scattered all over the country, necessitated by simultaneous broadcasting of important events, requires an efficient system of land lines. It was found that ordinary telephone lines did not fulfil requirements as to quality.