Fixed Resistor-Card Memory

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.