Upgrading BA11-N to BA11-S (was: Unibus/qbus wire wrap tool) - test-drb@ccmp.vtda.org

29 Sep 2014

...
  I have verified that the CD part of the backplane is
identical in both (the
...
  1983-84 Microcomputer Interfaces Handbook,
EB-23144-18, has pinouts for
 the CD
 part for both, and they are indeed identical). Alas, I cannot find detailed
...
  data on the rest of the H9273-A: neither the BA11-N
Technical Manual, nor
 the
 Print Set, is available online. (I found some old list email which
 indicates
 that someone named David Powell had a copy of the TM - does anyone know
 him?)

         Noel

Hi Noel, there are H9273/H9273A PCB layouts and wiring diagrams at pages
41-51 of the "PDP11/23 Field Maintenance Print Set". A Google search for
"MP00740_1123_schem_Oct81" will bring it up on Bitsavers.

Malcolm