Diode Gate B172

This document is a technical schematic for the Digital Equipment Corporation "Diode Gate B172" circuit board. The diagram illustrates an electronic logic gate configuration utilizing a series of diodes (D1 through D22) and transistors (Q1 and Q2) to perform signal conversion. It includes specifications for resistors, capacitors, and a conversion chart for the transistors and diodes used on the board. The schematic is intended for test and maintenance purposes for hardware manufactured in 1967.