For some reason my 2nd reply (via email) didn't appear. This: Update: Found it! It's short, I can scan and upload tonight/tomorrow. Manual PN 10281-90904 Jan 1983 Includes HP-IB commands, schematics, etc.
Incidentally, if anyone has the actual 10281A board they'd sell, I'm interested. And/or a whole, reasonable condition 1640B. Mine is in very poor condition. Which is not great, since it's mainly for 'vintage HP collection' reasons. Guy
