Pushbutton telephone apparatus with automatic dialing and combinational sequential control signalling capabilities

摘要

An electronic telephone apparatus employs a pushbutton key array having multilevel switch contacts and a manually and automatically controlled signalling arrangement for output signalling in both the dial pulse and DTMF (Dual Tone Multifrequency) tone signalling formats. The signalling arrangement includes a memory storage and an automatic sequential dialing circuit to transmit various predetermined combinations of dial pulse trains of one or more digits and tone sequences useful in multiple PABX (Private Automatic Branch Exchange) networks, long haul microwave communication links between distant points and redialing of "found-busy" numbers. The memory arrangemnt is provided for both the dial pulse and tone signalling circuitry and is controllable by a sequence initiate stage and an inhibit stage whereby the station apparatus operator selects the signalling modes, initiates the signalling and determines the timing of the signalling such as the interdigital and intertone spacing of individual digits or groups of digits by selectively inhibiting the automatic signalling sequence.