On Fri, Apr 17, 2020 at 9:52 AM Bill Gunshannon via cctalk <cctalk@classiccmp.org> wrote: > > I have been sorting thru a bunch of stuff in an effort to > clean the place up (Aren't we all doing that now with all > this time on our hands?) 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. > > Anybody familiar with this and able to identify it? > Anybody interested in it? It should fit in a USPS > Medium Flat Rate Box.
Sounds similar to a BA123 backplane which has 4 Q22/CD slots and 8 Q22/Q22 slots. But the BA123 is rather distinctive with a gap then a 13th slot where the M9058 Signal Distribution Board for the M7555 RQDX3 is installed. For example BA123 backplane part number 54-17507-01 / 50-17506-01 https://www.ebay.com/itm/DEC-QBUS-BACKPLANE-BA123-DEC-54-17507-01-PDP-11-MICROVAX/263251797600 https://i.ebayimg.com/images/g/LygAAOSwrP9Z2V7z/s-l1600.jpg
