DD11-B Engineering Change Order Log

This document contains a series of Engineering Change Orders (ECOs) issued by Digital Equipment Corporation in 1973 and 1974 for the DD11-B backplane. Key changes include:

• DD11B-A0001: Added a chassis ground wire.
• DD11B-00002 / DD11B-0002A: Addressed wire damage caused by sharp component edges and corrected the effectivity definition.
• DD11B-D0003: Added backplane wiring required to support the DU11-EA option.
• DD11B-00004: Provided a new power harness for specific PDP-11 systems with fifteen-pin power distribution.