ISO: schematics for Bunker Ramo BR2412

Josh Dersch derschjo at
Sun Sep 25 22:29:20 CDT 2016

Hi all --

I have myself a Bunker Ramo BR2412 12-bit minicomputer.  This is similar 
(but not identical) to the Nuclear Data ND812.  There are schematics / 
maintenance manuals for the ND812 on Bitsavers which have been immensely 
helpful.  The main difference between the BR2412 and the ND812 is that 
the BR2412 uses Intel 1103 RAMs (backed up by a big lead-acid battery) 
rather than core memory. (There are other more subtle differences, the 
ND812 used incandescent bulbs on the front panel, the BR2412 has LEDs).

I've been working on restoring this thing (which has been an interesting 
challenge -- there are 325 wire-wrap sockets with dodgy connections with 
the ICs to deal with) and I've been making steady progress, but I've 
finally reached a point in my debugging where the schematics differ from 
reality, as I get closer to the memory interface.  I can likely work 
things out by hand, but having a real set of documents would obviously 
be helpful.

I realize this is a long shot since it's a pretty obscure machine, but I 
thought I'd ask before I dive in too deep here. Oh, and while I'm asking 
for impossible things, if anyone has any *parts* for one of these, let 
me know -- I'm missing the TTY interface...



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