M592

This document is a proprietary electronic schematic diagram for the Digital I.O Device Select M592 (part number CS M592-0-1), developed by Digital Equipment Corporation in 1971, intended solely for test and maintenance purposes.

The schematic illustrates a complex circuit built with various electronic components, including:

• Integrated Circuits (ICs): Primarily DEC1074H50 and DEC1074HOO logic gates (indicated as E1, E2, E3).
• Transistors: Types DEC4258, DEC3009B, and DEC6534C.
• Diodes: Types D664 and D662.
• Passive Components: Numerous resistors (1/4W, 5% tolerance, various values) and capacitors (e.g., .01uF 100V 20%, 39uF 10V 10%).

The diagram shows multiple input lines (e.g., D1-D7, A1-H1, V2, M2, P2, N2, U2, T2, R2, S2) routed through combinations of logic gates and discrete components to generate various output signals (e.g., RI, UI, KI, PI, MI, L2). This suggests the board functions as a selection or decoding mechanism for input/output devices.

The document also includes:

• General Specifications: Details on component tolerances (e.g., resistors 1/4W 5%, capacitors .01uF 100V 20%) and IC power connections (Pin 7 to GND, Pin 14 to +5V).
• Power Rails: Indication of +5V and -15V supply voltages.
• Bill of Materials: A comprehensive list of all parts by DEC part number, description (e.g., Resistor, Capacitor, IC, Transistor, Diode, PC Board, Handle, Eyelets), and quantity.
• Conversion Chart: A table providing EIA equivalents for DEC transistor and diode part numbers (e.g., DEC3009B to 2N3009, D664 to 1N3508).