Solid state devices in the switching and line signalling equipment of the telephone networks

Problems arising due to the introduction of solid state devices into telephone networks have been discussed. A meter which measures the statistics of any stationary waveform has been developed. The use of this meter to study the statistics of the stationary noise in telephone systems has been demonstrated. A design of a line signalling relay set has been carried out using integrated circuits and other solid state devices. New circuit configurations have been used to ensure reliable operation.