I should have paid more attention - since it doesn't appear to have an CPU
control panel in the back, then we can guess that it must be a KDF11A 11/23
CPU and the four serial ports that you see are a DLV11J. No way of knowing
whether it's a real 11/23 or a 11/23+ without reading the M number off the
CPU card. It probably also has a BDV11, some amount of memory, a RQDX1 and
of course a TK/TQK50.
Bob