According to the article in the pic, that's an add-on for the RasterOps ColorBoard 364 FrameGrabber/VidCard I got on eBay. The RC364 has DA-15, S-Video and Composite connectors.
My initial reaction/WAG (not quite clueless, but fairly close to that) for the ADB daisy-chaining on the box would be text overlay or a sound sync or input setup? Neither Video Connection on the RC364 carries sound, which might explain the speaker/sound monitor? Dunno, have you got an educated guess, CelGen?
The product announcement jibes with the ©4/5/90 date/V1.01 ROM sticker on my 364. Manual is©1990, however the driver disk is ©1991.
edit:
HEH! Just followed your initial link, forgot about that thread. When I lost my password, I was alcoa for a while and it looks like I made the same guess. Same advice: Make the DuckGo with those parameters. I try not to use PersonalInfoHoover, but breaking that habit is tough going. :-/
My initial reaction/WAG (not quite clueless, but fairly close to that) for the ADB daisy-chaining on the box would be text overlay or a sound sync or input setup? Neither Video Connection on the RC364 carries sound, which might explain the speaker/sound monitor? Dunno, have you got an educated guess, CelGen?
The product announcement jibes with the ©4/5/90 date/V1.01 ROM sticker on my 364. Manual is©1990, however the driver disk is ©1991.
edit:
HEH! Just followed your initial link, forgot about that thread. When I lost my password, I was alcoa for a while and it looks like I made the same guess. Same advice: Make the DuckGo with those parameters. I try not to use PersonalInfoHoover, but breaking that habit is tough going. :-/