Connection of participants into telephone conference system - using comparison of signal levels to provide priority switching signal

摘要

The telephone conference system can have several telephone lines connected to it to permit bidirectional communication with several users. The loudest signal is given priority and a multiplexing circuit switches from one speaker to another. A number of participants in a conference are connected via two wire to four wire converters and amplifiers for transmission and reception to a large signal switching circuit. Amplifiers in the transmission circuits connect to full wave rectifier circuits to provide signals for large signal detectors. The detector outputs determine priority by comparison in logic circuits of the signal levels of all the user circuits. The outputs are applied to the switching circuit so that the appropriate signal paths are made.