BA11 mounting boxes
From Computer History Wiki
The BA11 is the name for a series of hex system unit backplane mounting boxes for the H960 series of 19"-wide racks produced by DEC. Although they were intended to be rack-mounted, many were available in table-top configuration as well.
The H960 racks provided 63" of vertical mounting space, divided into units of 10-1/2", which were further subdividable into a pair of 5-1/4" spaces. The BA11 mounting boxes were designed for these spaces.
They included:
- BA11 - the first, used in the PDP-11/20
- BA11-A - a late unit, used for the PDP-11/44
- BA11-D - used for the PDP-11/05
- BA11-F - used in the larger -11's like the PDP-11/45
- BA11-K - used to hold both CPUs as well as devices
- BA11-L - ditto
The -F was a 21" box, and the -L a 5-1/4"; the rest were all 10-1/2".
There were also several boxes in the BA11 series which held quad QBUS backplanes:
These were all 5-1/4" high.