Telephone call diversion appts. independent of contractual regulation - incorporates signal transmission controller responsive to ringing- and dialling-tone detectors and dual-tone multifrequency receiver

摘要

Calls on an incoming line (1) are forwarded on an outgoing line (2) to another subscriber at the same or a different location, via a signal-transmission, DC-level-setting and telephone-connection-matching circuit (5). A controller (6) connected between the two ringing-tone recognition circuits (4,4a) also operates a DTMF transmitter (S), and allows insertion of recorded speech, electronic music or other sounds. Loop currents on both incoming and outgoing lines are detected by suitable circuits (8,8a). ADVANTAGE - The appts. can be connected and used by any private telephone subscriber at usual rates for call forwarding, even at cheap rate.