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What backplane is this?

D

dfnr2

Experienced Member
Joined
Dec 6, 2011
Messages
466
Location
Dallas, TX
Hello,

A while back I picked up a DEC backplane on ebay. The description was not detailed, and the photos were not great, but it looked like a DEC PDP-8 or PDP-11 backplane, and I have cards for both, just waiting for a backplane.

I do not recognize this backplane, and searching for the marked part numbers doesn't yield anything. There is are stickers with part numbers. One indicates 70-14329 Rev E, and the other indicates 70-14245-00 Rev D.

I'm posting some photos below. Does anyone recognize this board? Or perhaps the part numbers indicate a certain line or products, if not something specific?

Thanks for any hints.

backplane-front.pngbackplane-back.png

Dave
 
WRT OP objective to host a "PDP-8", note that the 8/A backplane (in this case, a 620) can host an E/F/M as well ... just ignore the right-most column (partially filled) of connectors. Example with a few Omnibus modules inserted in attached pic. Note that the conventional order runs top-to-bottom, with the CPU modules at the top and various peripheral modules towards the bottom. In the 8/A the fifth column is used to support extended memory management.

WRT a "PDP-11" it makes a big difference what "cards" you have as almost all of the Unibus models require a very specific backplane. If you have a M7263 (KD11-D; PDP-11/04 processor) then you have the one case that can be used with a generic DD11 SPC backplane.

More likely you have Qbus "cards" in which case there's a lot more flexibility and backplanes are more easy to come by. Which modules do you have to work from?
 

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Thanks to all of you! I suspected it to be an 8/a backplane, but despite searching, I couldn't find a match. But this is clearly the same.

I have a set of 8/f cards, meaning the front panel uses LEDs. I have the full CPU set (without EAE, but with extended addressing), a 4K core, and Vince's 32K sram board, plus one of Roland's extended bootloader boards and his disk controller reproduction (currently bare). I hopefully will use this as the backplane and figure out a way to make a case.

BTW, my PDP-11 cards are Qbus cards. They are in storage, but I have a KDF11-BB, a couple of RAM cards (can't remember which), and some flavor of DLV-11. No disk controller.
 
dfnr2 said:
Thanks to all of you! I suspected it to be an 8/a backplane, but despite searching, I couldn't find a match. But this is clearly the same.

I have a set of 8/f cards, meaning the front panel uses LEDs. I have the full CPU set (without EAE, but with extended addressing), a 4K core, and Vince's 32K sram board, plus one of Roland's extended bootloader boards and his disk controller reproduction (currently bare). I hopefully will use this as the backplane and figure out a way to make a case.
Click to expand...
This backplane will work just fine in that application. It's just a beast of a boat anchor! As for a case, consider mahogany ... suitably finished and polished to a high gloss :->.
dfnr2 said:
BTW, my PDP-11 cards are Qbus cards. They are in storage, but I have a KDF11-BB, a couple of RAM cards (can't remember which), and some flavor of DLV-11. No disk controller.
Click to expand...
So an 11/23-in-waiting. The M8189 should work fine in any Qbus backplane that's 8 or 9 slots. If it's only 4 slots then you'll likely to have to patch it for 22-bit addressing; not difficult to accomplish but having only 4 slots will limit your configuration options ... but it sounds like you don't intend to go very far in that direction. http://retrocmp.com/projects/lsibox might give you some ideas, including storage.
 
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