Tektronix 4097 GPIB 8" Floppy Drive

One more follow up: I went ahead and pulled out the MK4027's on the Tektronix 4907 controller board and replaced them with MK4116's. Both were -3, 200ns parts. After double checking everything, I powered it up. This time -- no FAULT light. The "CLOCK" light was on, which indicates that the real-time clock in the controller needs to be set with the date and time. I powered the 4907 off, connected up the GPIB cable from the 4051, powered up the 4907, then the 4051, and typed CALL "SETTIME","05-14-09 19:18:00", and pressed RETURN, and the CLOCK light went out, and the 4051 was waiting for another command. I then did a MOUNT comment, and the drive loaded, the BUSY light flashed, and after a second or so, the 4051 was ready for another command. I then did a "DIR", and out came a listing of a bunch of files that were on the floppy. Looks like the 4116's are working perfectly, as is the rest of the 4907. Thanks to all for your encouragement and comments. Rick Bensene