Printed circuit boards (4), transistor, metal / fibreglass / plastic, Control Data Corporation, United States of America, 1966-1975
Four similar transistor circuit boards made by Control Data Corporation. They are logic units using silicon transistors and built with the "cordwood" technique, in which the components, using axial connecting leads, are connected into the facing pair of printed circuit boards.
These particular objects are probably from a CDC1700. One of which was in the network at the University of Sydney Basser Department of Computer Science.
The front of the boards are marked: ZT - ZT - ZO3 - VO2, and the back of the boards are marked: BYKTT - BYAKTT - AYHTT- 1794540IBYITT.