I have the short-lived low-end version of that unit in the cardboard box. I saw it in the Heathkit catalog, scraped some money together and bought it. I didn't see it in the next catalog. Mine is serial #8. This version of the unit only has half the memory of the one with the protoboard on the front: 256 bytes instead of 512 bytes. It also doesn't have the protoboard: just a keypad and six-digit hex display. There is a spot for an expansion connector on the inside, but I never did anything with it (I tried, though; I ordered a pair of 1Kx4 SRAMs from Radio Shack. 6 months later, _one_ of my two SRAMs arrived. The guy at Radio Shack didn't understand why I didn't want to buy just the one. The other SRAM never did arrive). I've not fired it up recently, but it worked last time I did. Roger Ivie ivie(a)cc.usu.edu