M304

This document is a proprietary and confidential schematic diagram for a Digital Equipment Corporation (DEC) "One Shot Delay" circuit, model M304, copyrighted 1969.

Intended solely for test and maintenance, the circuit design features:

• Integrated Circuits (ICs): DEC7440 (E1, E3, E5, E6), DEC7400 (E2, E7), and DEC7402 (E4), operating with standard TTL power (Pin 14 = +5V, Pin 7 = GND).
• Transistors: DEC3009B (equivalent to 2N3009).
• Diodes: D664 (equivalent to 1N3606).
• Resistors: Predominantly 1K (1/4W, 5%), with specific applications using 12.1K (1/8W, 1%) and 1.5K values.
• Capacitors: Generally 0.01 MFD (100V, 20%), and critical timing capacitors specified as 120 MMF (picofarads), 5%.

The document provides a detailed circuit layout and a conversion chart for DEC-specific transistor and diode part numbers to standard EIA equivalents.