16K (4116) - at least, in the Alto II I have images of. Maxc used 1103's (1K), but they were a few years before the Alto. I got out my August 1971 -11/20 price sheet, and that sounds about right. The machine had "24K bytes of core memory .. and a disk with 1K blocks (512K bytes ... a single .5 MB disk .. every few hours' work by the typists meant pushing out more information onto DECtape, because of the very small disk." ("The Evolution of the Unix Time-sharing System"): 11,450 Basic machine CPU + 8KB memory 6,000 16KB memory (maybe 7,000, if MM11-F) 4,000 TC11 DECtape controller 4,700 TU56 DECtape transport 5,000 RF11 controller 9,000 RS11 drive 3,900 PC11 paper tape ------- 44,050 (Although Bell probably got a discount?) The machine later had an RK03: https://minnie.tuhs.org/cgi-bin/utree.pl?file=V1/u0.s but that wasn't there initially (they are 2.4MB, larger than the stated disk); it cost 5,900 (RK11 controller) + 9,000 (RK03 drive). Also, no signs of the KE11-A in the V1 code (1,900 when it eventually appeared). The machine had extra serial lines (on DC11's), but they weren't much; 750 per line. Memory was part of it. The -11/20 used core; $9,000 for the memory alone. Also, the machine was a generation older, the first DEC machine built out of IC's - all SSI. (It wasn't micro-coded; rather, a state machine. Cheap PROM and SRAM didn't exist yet.) Noel