M949

This document is a proprietary schematic diagram, copyrighted 1970 by Digital Equipment Corporation, for the M949 Indicator Cable Connector. It is intended for test and maintenance purposes.

The schematic illustrates multiple identical indicator lamp driver circuits, each typically consisting of a resistor, capacitor, and a DEC6531 transistor, connected to various switch and common lines (SW1-SW9, H2 SW COMM #1, N2 SW COMM #2, V1 SW COMM #3). These circuits also show connections to a flexprint leading to an M950 module.

The document specifies the standard component values: resistors are 3.3K, 1/4W, 5%; transistors are DEC6531 (with MPS6531 as a conversion); and capacitors are 470 PF, 100V, 5%. It also defines the "FA" and "FB" lines in relation to the component and etch sides of the M949 and M950 boards.

Supporting information includes a detailed parts list for the assembly (including the etched circuit board, module ECO history, assembly/drilling hole layout, and X-Y coordinate hole location), a transistor and diode conversion chart, and a visual layout of the discrete components (Q1-Q9, C1-C9, R1-R9).