PDP-12 Restoration at the RICM

We spent a few more hours on the PDP-12 today... With the machine just powered on the stack 0/1 regulator output was 20.04V. With tune3 running in field 1 and testing field 0 the stack 0/1 regulator output was 19.93. No memory errors were reported. When the voltage was adjust up to 22.5 and down to 19.96 we saw a few failures. We split the voltage range and adjusted the regulator output voltage to 21.3. No errors were observed when testing field 0 or field 1. We successfully loaded and ran 10 passes of: MAINDEC-08-D1B1 Memory Address test. MAINDEC-08-D1B2 Memory Address test. MAINDEC-08-D07B-D Random ISZ test. We ran these diags without errors MAINDEC-12-D0GA-A_Tape_Quickie MAINDEC-12-D8AB Relay Register Test -- Michael Thompson