W700

This document is a proprietary schematic diagram for a "SWITCH FILTER W700" electronic circuit, developed by Digital Equipment Corporation (DEC) in 1964.

Key features and components include:

• Purpose: Furnished for test and maintenance purposes.

• Components: Primarily built with resistors, diodes, and capacitors.

  • Resistors: Generally 1/4W, 5% tolerance, with specified values (e.g., 1,200 ohms, 7,500 ohms). Some are 10% tolerance (1,000 ohms).
  • Diodes: Identified as D-664 (equivalent to IN3606) and D-662 (equivalent to IN645).
  • Capacitors: Specified in MFD (microfarads), with values such as 6.8 MFD and 0.01 MFD.

• Circuit Structure: Features multiple input stages (labeled F, J, L, N, R, T) each with input resistors, a pair of diodes, and a capacitor. These stages feed into a common bus, leading to an output stage that includes a cluster of D-662 diodes and a "-3V STRATE" reference.

• Power Supply: Designed to operate with a B-15V supply and a ground reference (C,V GND).

The overall design suggests a digital logic or signal conditioning circuit, characteristic of early digital computing hardware.