At 11:21 PM 9/6/05 -0700, Al wrote: Bingo! That's it. Here's some more info about the boards in the pictures for anyone that's interested. Picture name Board name notes ---------------------------------------------------------------------------- ---------------------------- Clock - TTY Controller = Line Frequency Clock CCA on LH side TTY Controller on right ICs dated 1974 PTR Interface = Paper Tape Reader - Punch Interface ICs dated 1976 CPU Lo = CPU LO ICs dated early 1975 Passed Processor Test 1994 Current Loop = Line Frequency Clock (right) & Current Loop Interface (Left) ICs dated 1974 & 1975 PT Interface = Paper Tape Reader - Punch Interface (2nd pair) ICs dated 1976 CPU Hi = CPU HI ICs dated 1973. Passed Processor Test 1994 & OK 5/21/1980. Universal = Universal Logic Board ICs dated 1975 CPU Hi 2 = CPU HI (second board) ICs dated 1972 to 1974. Passed Processor Test 1994 core = ??? Almost certainly core memory Passed Memory Test 1994. ICs dated 1974. CPU Lo 2 = CPU Lo (second board) ICs dated early 1975 Passed Processor Test 1994 Joe should be something to go