In case you're not already aware of it, the 4041 is about the same size and shape as the HP 9915 and it serves the same function (a small dedicated HP-IB controller). One major difference is that the 4041 has a small LED display and a calculator type keyboard so it is possible to operate it directly. The HP 9915 has no display and only a couple of function keys so it's impossible to control it by itself. IIRC you can also operate the 4041 via a terminal. I'm not sure but I seem to remember that you need a terminal ROM set to make that work. But I'm pretty sure that the terminal was auto detected and you didn't need to use a keyboard or any kind of tape to force the 4041 to use the terminal. I'm not sure but I think the serial port(s) were optional so you may not have one. I've had a lot of Tek 4041s over the years and even had two of the DDUs (Disk Drive Units) but I've only ever found ONE keyboard. I used to have a full set of manuals for the 4041 including the service manual but I gave all of it to Mike Haas and I think he's since sold them. I think my buddy in Sanford probably has manuals for it but I don't know when I'll be over in that area again. Joe At 12:40 AM 7/21/05 +1200, you wrote: