R111

This document is a proprietary circuit schematic for a "DIODE GATE RIII" developed by Digital Equipment Corporation, copyrighted in 1964. It is intended for test and maintenance purposes only.

The schematic details a logic circuit featuring three main, similar gate sections, each employing a DEC3639 transistor (equivalent to 2N3639), various D-662 (IN645) and D-664 (IN3606) diodes, and numerous resistors. Key resistor values include 100,000, 15,000, 7,500, and 1,500 ohms, all specified as 1/4W and 5% tolerance unless otherwise indicated. The circuit also includes a .01 MFD capacitor.

Power connections are specified as +10V, GND, -15V, and -3V. The drawing number is RIII-O-1, Revision F, and it indicates a printed circuit board revision "SIB" for the DGL board. A component conversion chart provides EIA equivalents for the DEC-specified transistors and diodes. The document was drawn on May 15, 1964, and checked/engineered on May 25, 1964.