Some corrections to my post regarding the console LED behavior.
Voltage levels on the CPU backplane are still good whne the 2 CPU boards are installed in the backplane, but the processor is not responsive to the switches on the console panel. The RUN LED is on, ADDRESS/DATA are all off. When the HALT/ENABLE switch is in the HALT position and START is toggled ("reset"), the RUN goes off and the ADDRESS/DATA LEDs all go on. LOAD ADDR, EXAM and CONT have no response. When I set HALT/ENABLE switch to ENABLE and toggle START, the RUN LED goes on and DATA/ADDRESS LEDs go off, except LED "0". greetz, - Henk, PA8PDP