This device, which may be acoustically-coupled to any conventional telephone handset, generates coded tone sequences representing alphanumeric characters. The full ASCII character set, coded with parity, is used, and all 128 symbols available for selection are displayed on the device in a small electronic ``keyboard.'' The transmitted tone sequences correspond to those generated by most Teletype-Dataphone terminals in typical time-sharing systems. In operation, the user dials the remote machine and then inputs messages, character-by-character, by pointing at the selected symbols on the keyboard with a hand-held selection ``pen,'' in a hunt- and-peck fashion. It is assumed that this device would be used to communicate with a machine which has voice answer-back capabilities.

A fixed or read-only memory, consisting of a stack of paper or plastic punched cards, each containing an interconnected array of printed resistors, is discussed. The cards are compatible with conventional keypunches, and information is recorded on each card by the punching of a pattern of holes, each of which severs an appropriate connection. An interconnection method, which involves the injection of molten, low-temperature solder alloy into special channels in the stack, is described. This technique provides all card- to-card interconnections simultaneously. It is shown that the memory can be operated in a content-addressable or associative mode. Experimental results, dealing with resistor silk-screening and card stack construction and operation, are presented.