CIRCUITRY FOR SUPERIMPOSING SMALL, LOW ENERGY SIGNALS AND LARGE, ESSENTIALLY HIGHER ENERGY SIGNALS

摘要

A circuitry is disclosed for superimposing small, low energy (2) and large substantially higher energy (3) signals, in particular for trans- mitting speech signals with a remote supply direct signal for a receiving circuitry or with a high energy alternating Signal, for example a call al- ternating voltage for signalling. In Ihis circuitry is provided an opera- tion amplifier (I). One pole of the source that supplies the small signal is connected to one input of said operation amplifier whose operation- al voltage inputs arc connected to a voltage supply source. In order to allo w low energy, weak signal, such as speech signals, and high energy signals and direct voltages to be transmitted by such circuitry over a subscriber line by means of simple components, the second pole of the small signal source (2) is linked to the second input of the operation amplifier (I) and one pole of a higher energy signal supply source (3) is linked to one pole of the voltage supply source (V).