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G657/H-228 Core memory boards for PDP-11/60?

Schroeder

Experienced Member
Joined
Apr 27, 2018
Messages
79
Location
Germany
Hi!

I purchased a box of DEC boards not really knowing what some of the cards is about. Most of the boards is actually usable for my restauration projects but this bundle I'm not sure.
Some Unibus systems I do have such like 11/24 and 11/44 but this boards seem to be for a PDP-11/60.

Is there anyone out there actually using and/or running a PDP-11/60? Or are these boards something to be on display, at least they are really nice looking?

Here are some pictures, the H-228/G657 Sandwich and an extra H-228 board with a broken seal.

Cheers
Peter
 

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According to DEC marketing/sales documentation (Modules and Options Lists) the MM11-YP was the only use of the H228 32-Kword 18-bit 14-mil core stack, and the MM11-YP was only sold in 11/04 and 11/34 configurations. In fact, my bundle of 11/34A documents (FMPS) as distributed by DEC includes documentation for the MM11-YP as well as the smaller MM11-DP.

Standard PDP-11/60 configurations used the MM11-W/WP as part of the MF11-W/WP subsystem/system unit. That incorporated the H224C 32-Kword 18-bit core stack, usually in pairs.

Anyway, "this one" is working on an 11/60 restoration and IMO your modules should be put to work (and I would), not just admired as technology-art from an ancient age :-}.
 
As far as I can recall, any 18-bit Unibus system (possibly with the exception of the 11/45/50/55) would be just using any Unibus memory. They should all work in all machines.
They are not model specific.
Also, the 22-bit Unibus machines (11/24 and 11/44 basically) are the exception, as they have special slots where 22-bit aware memory cards needs to go.

And of course, the 11/70 don't normally have memory on the Unibus, but it can, in which case it's just standard Unibus memory we're talking about.
 
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