Selective connection method for telecommunication terminals

摘要

The method involves carrying an identification signal of a terminal to a called terminal using a 25/50 Hz calling signal. The called terminal shares the transmission line with the calling signal. The identification signal is analysed in the called terminal and from this identification signal the line is engaged by the called terminal. Preferably, the terminal identification signal gets an impulse from the first calling signal and is send asynchronously with the calling signal to the terminal. From each calling signal the identification signal gets an impulse and is sent.