This is a Spectra Logic – Spectra 20 controller which provides both SMD and Pertec interfaces via DG device emulation.
I am very happy to finally get my hands back on one of these controllers as I used to repair this PCB and it’s ‘plus’ counterpart in my first paid job.
This example is in reasonable condition considering it was salvaged from a second hand store!
More on this PCB in due course once I have bench tested it (Need a Pertec Drive First!).