Mm8-aa & Mm8-ab Field Installation & Acceptance Procedure

This engineering specification details the installation and acceptance procedures for the MM8-AA (8K) and MM8-AB (16K) core memory modules used with PDP-8A 400 or 500 series processors.

Summary of procedures:

• Inspection: Upon unboxing, technicians should check for physical damage, ensure all documentation and hardware are present, and verify that the stack board is securely fastened to the baseboard.
• Installation: The process involves configuring field selection jumpers based on the memory location/starting address (as outlined in the provided configuration tables) and installing the module into the processor's omnibus (slots #4 through #8) while power is removed.
• Acceptance Testing: This includes:
  • Power Fail Check: Verifying that memory contents are not altered by a power cycle.
  • Operational Check: Running the 4-32K memory diagnostic (08-DJMMA-PB) for a minimum of 10–20 minutes.
  • Memory Margins: Using a specific field service test fixture to stress-test the memory strobe and X-Y current parameters using the diagnostic software. Note: The test fixture must not be used on G649 "C" etch modules.