8/S Replica (was: TTL CPU Re: IMSAI style C&K 7101 switches)

Apologies if this appears twice, but it looks like hotmail ate my message again. From: "Grant Stockly" <grant at stockly.com> I've got modern CAD drawings for a replica backplane for the 8/S, if that's of interest. That and about a dozen module drawings will let you build a replica (given enough cash). Of course, to be authentic, you'd export the netlist and wire wrap the backplane, but that's a preposterous amount of error-prone work. I do have a Perl script to generate a wirelist, though, if someone wants to try it :-). Even though the modules are all single-sided, that's a lot of wire-wrapping! The replica also uses an SRAM memory module, instead of the original core. The SRAM module is double height (to get enough pins), and standard DEC modules are used to interface to it. I haven't done anything with the slots freed up by replacing the core subsystem. (There might be enough room to integrate a TTY controller!) I do have the TTY controller backplane drawn, too. Oh, and the memory expansion above 4K is also still a separate backplane (which I haven't drawn). I do know of a guy in Australia who's done some work on replicating the Rxxx modules. Generally, I think the 8/L backplane is a more promising starting point, though it lacks the cachet of being all-transistor (and the DEC modules use dated, hard-to-find TTL). Of course, the memory expansion for that is *also* another backplane (which I haven't drawn). Vince