Going through some boxes of documentation, I found some rather obscure DEC “Field Service Tech Tips” (and DEC uNote #043) that relate to the RQDX controllers.
uNote #043 is already online elsewhere, but I had not seen these Tech Tips before.
The 4 documents that I have scanned are:
DEC uNote #043 (RQDX Controller Status/Information)
DEC Field Service Tech Tip No. RQDX2-TT-01 (RQDX2’s in 11/23 and 11/73)
DEC Field Service Tech Tip No. RQDX2-TT-02 (RQDX2 Tips and Rev History)
DEC Field Service Tech Tip No. 610QM-TT-06 (RD51/52/53 Survival tips)
These are available here -> http://avitech.com.au/?page_id=951