I have a Kaypro 16 that needed a new power supply. I salvaged one from another 16 and got it working but couldn't get the hard drive to work. This unit came from factory with 640K and a 20 meg hard drive. After searching hign and low for the solution I finally did a low level format on an older XT runnning PS DOS 3.2/ It worked! However the original dos 2.1 didn't like the LL format but I just upgraded the system to the DOS 3.2 and it worked well. Complicated solution but a solution none-the-less.