BA11-SB Mounting Box

The guts of the system are housed in this enclosure which simply slides into a cover mounted in the cabinet. The BA11-S is home to a H7861 power supply (and its AC input box at the back), the system's H9276-A 9-slot Qbus backplane (stamped 12 January 1984) and two large cooling fans.

The BA11-SB Mounting Box

Top view

Cooling fans

The various modules which make up the system are inserted from the rear. On the front is a simple (very simple by PDP-11 standards!) control panel which is used to halt or restart the system. The AUX power switch on the right can be used to control the power controller mounted in the bottom of the cabinet, allowing the whole system to be started at the press of a button.

Rear view

Close-up of the front panel.