R107

This document is a proprietary circuit schematic for the Digital Equipment Corporation (DEC) "Inverter R107", copyrighted in 1964 and revised to 'J'.

The schematic details a multi-stage inverter circuit, featuring seven primary transistor stages (Q1-Q7), each with associated resistor-diode networks and power connections (+10V, Ground, and -15V). It also includes a "STRATE" section with additional diodes and a resistor, and a capacitor (C1).

Key component specifications are provided:

• Transistors: DEC 3639B (equivalent to EIA 2N3639)
• Diodes: D-664 (equivalent to EIA 1N3606) and D662 (equivalent to EIA 1N645)
• Resistors: Generally 1/4W, 5% tolerance, with specified values ranging from 100,000 ohms down to 1,500 ohms.

The document explicitly states that it is furnished for test and maintenance purposes only and that the circuits are proprietary. It also notes that the printed circuit board revision for the DGL board is SIA.