On Friday (02/20/2009 at 02:16PM -0800), Al Kossow wrote: Hey... cool. When I was in highschool, I worked several summers for Multi-Tech Systems, Inc. here in St. Paul. Most people probably know them for their modems... In about 1979, we were building a clone of an R2E system-- or at least there was some business arrangement that I did not know the details of-- but this system was a Z80 based, S-100 design with integral CRT, dual floppy (Micropolis 1015 II with Micropolis controller at first) and it ran CP/M. The cabinet was like 1/4" steel and weighed an absolute ton. I remember having a lot of problems with the power supply transformer (which also weighed a ton) being too close to the deflection coils on the CRT and it causing a beat in the video. In the end, I think they fixed this by getting the CRT controller to actually use a 60 Hz vertical refresh instead of something that was slightly off. Anyway, the CPU board was laid out by hand-- I mean, like, drawn with a pen-- so you have traces that follow round corners and have no uniform spacing between them when they are bussed. It looks really sad. But-- it mostly worked... and in fact, I still have one of these CPU boards, the hideous power supply, a pair of the Micropolis 1015-II drives and the controller. The whole thing is built into a wood box with a formica front panel. I ended up writing a lot of BIOS / PROM code for that machine before I was even out of highschool. In the formica computer, I used the serial port for the console and connected an H19 terminal to make a decent CP/M system from it. I'll fire this thing up someday soon... I'm sure the crappy power supply will need some work. I do still have schematics, a user manual and a lot of software on 16-hole, hard sector floppies. At one time, I believe Multi-Tech and R2E America shared the same office on University Ave-- or someone at Multi-Tech was the R2E connection. It might be interesting to track down that history in a little more detail. Chris -- Chris Elmquist mailto:chrise at pobox.com