On 17/04/2020 17:52, Bill Gunshannon via cctalk wrote:
I found a backplane. It says
Digital on it but does not have an H- number. I also
don;t find it listed in any of the lists I can find on
the web.
It has 8 A-B slots and 4 C-D slots. the Four C-D are on
the bottom half of the backplane. I am assuming it is
18 bit and the C-D were intended for things like the 2
board RL controller.
Is it quad height or hex height? Is there a picture anywhere?
It sounds a bit like an H9278-A, which is a 22-bit 4 x 8 (ie quad
height, 8 rows) backplane for a BA23 box. That has a mixture of Q22 and
CD in part and Q22 on the rest, but the rows with CD are the top rows.
http://www.dunnington.info/public/PDP-11/QBus_chassis
--
Pete
Pete Turnbull
