http://www.retrotechnology.com/restore/vcfrepair_sep19.html I was going to post about my PDP-8/A repairs at the recent workshop; the linked WEb page has details. When I read Evan's post about his LEGO Logo Robo go-go work, I added some photos and links about that, to my Web page. I looked with effort on the Web for "da schematic" for the motor controller, the thing that was "jumpered" in posted discussion. I was surprised to NOT find it. There's info on the Apple II interface card already, as discussed. Odd someone with skills, hasn't drawn this already. There's the usual reasons, mostly like these things are already available for tens of dollars used. Ah - this Web page is informative: http://lukazi.blogspot.com/2014/07/lego-legos-first-programmable-product.htm... Regards, Herb "copper trace" Johnson -- Herbert R. Johnson, New Jersey in the USA http://www.retrotechnology.com OR .net preserve, recover, restore 1970's computing email: hjohnson AT retrotechnology DOT com or try later herbjohnson AT retrotechnology DOT info