M7009

This document is an Engineering Change Order Log (ECO) from Digital Equipment Corporation concerning the M7009 Video Display Interface, used with the PDP-11/05 processor.

It details two main change orders:

1. M7009-B0001 (July 1973): Addresses multiple issues with the M7009 board, including:

   • Errors in the Assembly Hole drawing.
   • Intermittent UNIBUS hangs caused by the M796 component.
   • Incorrect values for resistors R10 and R11 in the Parts List.
   • Errors in the Circuit Schematics. The correction involves restoring the drawing, modifying "TIME OUT" to inhibit RESTART and clear M7821, correcting the resistor values (R5, R10, R11 to 5.11K ohms), and fixing schematic errors. A two-part rework procedure is outlined, with Part 1 specifically applying to "C" etch revision boards. All M7009 units require this rework, which is estimated to take 2.5 hours to install and test, with associated costs for documentation and parts.

2. M7009-B001A (July 1973): This is a correction supplement that clarifies the wording of the M7009-B0001 change. Specifically, it reiterates that Part 1 of the rework procedure only applies to "C" etch revision boards and revises the "BREAK-IN EFFECTIVITY" wording.