Electronic pushbutton dialling for telephone - uses wired memory containing emergency numbers and addressed by supplementary button

摘要

The telephone with push button dialling is powered from the line. A memory circuit contains numbers for emergency calls which are activated by supplementary push buttons. A telephone with electronic pushbutton dialling has a keyboard for entering the dialling numbers. A clock circuit has output frequency which permits maximum dialling speed to be achieved. A parallel series converter ensures that dialled numbers passing via a memory enter the line circuit. Emergency numbers are contained in a wired memory which is addressed by supplementary buttons. This information enters the converter directly to pass onto the line.