G7000

This document is an engineering drawing (DCS G7000-0-1, Revision B) from Digital Equipment Corporation, dated December 15, 1972, for an I/O Bus Terminator #1 designed for a PDP-10 computer system.

The document contains a circuit schematic and a detailed parts list.

Key features of the document:

1. Circuit Schematic:

   • Shows the interconnection of components forming the terminator circuit.
   • Features two main integrated circuits (E1 and E2), identified as "DEC 2501". These appear as diode arrays on the schematic.
   • Includes various diodes (D1-D9), resistors (R1-R5), and capacitors (C1-C6).
   • Illustrates connections to multiple bus lines (e.g., AD, AE, AH, AM, BS, BT, BV) and power supply rails (-0.7V, -2.8V, -15V, and Ground).

2. Parts List:

   • Provides a comprehensive list of all components required, including their quantity, reference designation, description, and part number.
   • Highlights include:
     • Two DEC 2501 ICs for E1 and E2.
     • Nine diodes: Diodes D5-D9 are specified as D662, and D1-D4 as D664.
     • Five resistors, primarily 1.5K Ohm, 1/4W, 5% carbon composition.
     • Six capacitors, comprising two 39µF 10V 10% tantalum capacitors (C4, C5) and four 0.01µF 100V 20% disc ceramic capacitors (C1, C2, C3, C6).
     • Other items such as a flip-chip handle, Faston tabs, eyelets, and the etched circuit board.

3. General Notes:

   • Specify common characteristics for components: all resistors are 1.5K ±5% 1/4W C.C., and general notes for capacitors and diodes are provided (with specific parts list entries overriding these defaults).
   • Reiterates that E1 and E2 are DEC 2501 components.

4. Semiconductor Conversion Chart: Translates internal Digital Equipment Corporation diode numbers to industry standards (D664 = 1N3696, D662 = 1N645).

The document is a complete technical specification for the manufacture and assembly of the I/O Bus Terminator #1.