Transistor and Diode Conversion Chart

This document contains the engineering schematic for the M663 50 Ohm Bus Driver circuit board, developed by Digital Equipment Corporation in 1971. The content includes a detailed circuit diagram, a list of electronic components (resistors, diodes, transistors, capacitors, etc.), and a conversion chart for transistor and diode part numbers (e.g., D664 to 1N3506). This document is designated for test and maintenance purposes.