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legalize
September 4th, 2016, 04:32 PM
I have a Nuclear Data 812 that I pulled out of the Black Hole surplus store before they closed. There is technical documentation on bitsavers and I'm aware that there were some Bunker-Ramo machines that were similar or rebadged from the Nuclear Data brand. There was a batch of manuals on ebay that sold in the past year or so and if someone on here purchased those, it would be great if we could get them scanned onto bitsavers. I'd also love to hear from any other ND machine owners.

fvzappa
September 27th, 2016, 10:52 AM
Somehow I missed this post (I just posted my own request for information... how awkward).

I have a pair of BR2412s (the Bunker-Ramo variant of the ND812 that you mentioned). I'm working on restoring one of them (the other is a clear parts machine) and making slow progress -- it's now showing signs of life and I'm now trying to get the memory working. This is more of a challenge, because the only docs on Bitsavers are for the ND812 which had core memory -- the BR2412 uses Intel 1103s so I have no schematics.

I'm also looking for a TTY interface, neither of my machines have one fitted. And I'm missing one of the I/O bus terminators...

Al Kossow
September 27th, 2016, 11:31 AM
Somehow I missed this post (I just posted my own request for information... how awkward).

I have a pair of BR2412s (the Bunker-Ramo variant of the ND812 that you mentioned). I'm working on restoring one of them (the other is a clear parts machine) and making slow progress -- it's now showing signs of life and I'm now trying to get the memory working. This is more of a challenge, because the only docs on Bitsavers are for the ND812 which had core memory -- the BR2412 uses Intel 1103s so I have no schematics.

I'm also looking for a TTY interface, neither of my machines have one fitted. And I'm missing one of the I/O bus terminators...

Just to add my 2 cents, I have an ND812 that was stored in a barn (serious rodent nesting but no urine damage)
The sockets they used are crap. Of course, as Josh mentioned, the entire CPU is wire-wrapped.

Sadly, I don't know of anyone who has software for them.

Al Kossow
September 27th, 2016, 11:33 AM
the BR2412 uses Intel 1103s so I have no schematics.


1103 memory systems weren't very good when they were new :-(

Al Kossow
September 27th, 2016, 11:34 AM
1103 memory systems weren't very good when they were new :-(


if you get a chance, I'm curious what the innards look like.

I should shoot some of the ND812 now that I've cleaned it up

fvzappa
September 27th, 2016, 11:44 AM
Just to add my 2 cents, I have an ND812 that was stored in a barn (serious rodent nesting but no urine damage)
The sockets they used are crap. Of course, as Josh mentioned, the entire CPU is wire-wrapped.

Yes, the sockets are quite bad (although I heard rumor that the original runs used even *worse* sockets, apparently they were blue in color...). There are two saving graces on them: They're gold plated (so at least they don't seem to get too corroded), and the covers can be removed to allow cleaning. I've gone through all 325 of them and cleaned and tightened the socket brushes. I also cleaned all 322 ICs (there are 3 empty sockets) by scraping the crud off the legs gently with an xacto knife blade. It's now working enough that I can examine memory, but everything's coming back as all 1's so I have some time yet to spend on the memory...



Sadly, I don't know of anyone who has software for them.


I haven't found any either, so I'm not *entirely* sure why I'm going through this exercise, especially given what a pain this machine is in every respect. Maybe just because it's there...

legalize
September 27th, 2016, 12:51 PM
I believe my machine has core memory, so there might be something stored in there. It had a dual 8" floppy drive, but no diskettes were ever found. They were probably tossed into a pile of junk 8" diskettes and forever separated from the machine. If you ever had the joyful experience of visiting the Black Hole, you'll understand what I mean :).

fvzappa
September 27th, 2016, 08:46 PM
if you get a chance, I'm curious what the innards look like.

I should shoot some of the ND812 now that I've cleaned it up

Here's a few pictures:

33462334633346433465334663346733468334693347033471

As of this evening, the memory is responding; the Vss supply for the 1103's was at 0.5V and was being dragged down by something on one of the memory boards; I replaced it with one swapped in from the spares machine for now. A few bits are getting flipped on the way into the memory, but it's a good start...

MattisLind
September 28th, 2016, 12:38 AM
Sadly, I don't know of anyone who has software for them.
It isn't so that the ND4420 and ND4410 systems are based on the ND-812? Reading various documents indicate so. In that case the ND4420 software I imaged (http://bitsavers.informatik.uni-stuttgart.de/bits/NuclearData/ND4420/ND4420_paper_tapes.zip) a couple of years ago could be of use for ND-812 owners. ORCAL should be a "Oak Ridge Calculating Language"

Al Kossow
September 28th, 2016, 03:19 AM
It isn't so that the ND4420 and ND4410 systems are based on the ND-812? Reading various documents indicate so. In that case the ND4420 software I imaged (http://bitsavers.informatik.uni-stuttgart.de/bits/NuclearData/ND4420/ND4420_paper_tapes.zip) a couple of years ago could be of use for ND-812 owners. ORCAL should be a "Oak Ridge Calculating Language"

that's good news

for giggles, do a google search for 7021-01-008-0943

legalize
September 28th, 2016, 08:22 AM
I had some pictures of mine on picasaweb, but google has ruined that and made all my pictures private, so I have to migrate them somewhere else.

fvzappa
September 28th, 2016, 12:55 PM
It isn't so that the ND4420 and ND4410 systems are based on the ND-812? Reading various documents indicate so. In that case the ND4420 software I imaged (http://bitsavers.informatik.uni-stuttgart.de/bits/NuclearData/ND4420/ND4420_paper_tapes.zip) a couple of years ago could be of use for ND-812 owners. ORCAL should be a "Oak Ridge Calculating Language"

Cool! I knew of the ND4420/4410 and that it was built around the 812, but I didn't know any software had been recovered for it. Definitely something to play with. Someday, when this thing is working again...

Thanks!

fvzappa
October 2nd, 2016, 11:24 PM
Just a small update for those who might be interested -- as of this evening, the BR2412 is correctly executing instructions! I haven't tested everything yet (and since as far as I know, no official diagnostics have been archived, I'll have to write my own...) but single and double-word memory instructions work, as do the operate codes I tried.

Now I just need to track down a TTY interface (or build my own, more than likely -- that should be fun) and it'll be a real computer again!

legalize
February 13th, 2017, 12:51 PM
Based on bitsavers documents, I wrote a wikipedia article for it:

https://en.wikipedia.org/wiki/ND812

tingo
February 19th, 2017, 09:28 AM
Based on bitsavers documents, I wrote a wikipedia article for it:

https://en.wikipedia.org/wiki/ND812

Thank you.

legalize
February 19th, 2017, 12:31 PM
After digging into the instruction set, it always strikes me as odd when people refer to this machine as a "PDP-8 clone". The instruction set is very different from a PDP-8. About all it has in common is a 12-bit word length and the funky "jam the return address into the first location of the called subroutine".