Univac 9400 modules

typical board/typical module

This is a typical modul from the system. The DTL-IC's are clearly visible. Around every IC diodes are arranged which were usually executed as logical AND gate. Along this way a lot of different "logical chips" could be constructed. Actually some transistors were integrated in the IC, so the difference to the second-generation calculators is very low. Many modules from the system were still built with discrete transistor technology. The complete tape devices are from the mid 60s, so they are built without integrated circuits.