Anyone have docs for a Digital Engineering Retro-Graphics ("VT640") board?

Hi, All, Jack Rubin sent me a Retro-Graphics upgrade board and cage that seem to have had an unpleasant interaction with mud daubers (I only have the boards, but the report is that the PSU of its former host did not survive). I'd like to clean an resurrect it, and I'd like to find any tech docs to go with. The closest I've found so far is a manual on Bitsavers for a version of the product for an ADM-3A terminal: http://computer-refuge.org/bitsavers/pdf/digitalEngineering/RG-512_Users_Ma… I found a query from John Wilson (D-Bit) some months back where he's seeking a programmers' manual, so it appears there are more questors than answers. Does anyone have anything on this device? It's a DEC-quad-height-sized card, with connectors appropriate for a VT100 enclosure, a few cables (PSU and data to/from the main VT100 board) and a metal cage, possibly just the standard DEC cage from a VT100. I think I can see how to plug it all in, but beyond cleaning and checking for dead shorts, I'd like to know something about it before I apply voltage. Some very nice photos can be found here: http://www.fairlightcmi.com/VT640-board-set-eBay-photos.html Googling has so far only returned references to its use with the Synclavier II synthesizer (and its modern replacement, a "VT640" emulator for MacOS X) and various science and engineering apps from the heyday of VMS and dumb terminals. No technical data beyond a few control sequences. I know how to drive a Tektronix 4000-series graphics terminal (and have some nice Tek files from some recent research on my Tek 4105), but I'm really looking for hardware docs more than just lists of command sequences. Thanks for any assistance -ethan