W106

This document is a detailed electrical schematic for a module identified as "P.I. REQUEST GRANT W10G," copyrighted by Digital Equipment Corporation (DEC) in 1971. It depicts a complex logic circuit likely designed for control or interface functions within a larger computer system.

Key features and functional blocks of the module include:

1. Logic Gates: Various "AND" gates, such as a "Non-Lock-Up 'AND' Gate," a "Level Restoring 'AND' Gate," and a "Device Grant 'AND' Gate," implemented using discrete transistors (e.g., DEC30098, 2N4258) and diodes.
2. Polar Relay (K1 - Midtex): A central component with "break-before-make" contacts, controlled by differential current, suggesting its role in switching, latching, or sequencing operations (e.g., power or signal routing).
3. Power-Off Bypass: A circuit designed to manage conditions during power transitions.
4. Power OK Detector: A circuit to monitor the status of the power supply.
5. Inputs and Outputs: It accepts "JOB GRANT IN, T2" and "DEVICE INTERRUPT, U2" signals and provides "V2, JOB GRANT OUT" and "E2, DEVICE INTERRUPT START" outputs.
6. Power Rails: The circuit operates using multiple voltage supplies including +3.5V, +5V, -5V, -15V, and -0.7V.

The schematic also includes a "Block Schematic of Module" providing a high-level logical overview, and a comprehensive "PARTS LIST" detailing all components (transistors, resistors, capacitors, diodes, and the relay) by part number and quantity. The document states it is proprietary to DEC and intended for test and maintenance purposes.