Is the Disk II card dead?
right? Try removing the drive which was connected incorrectly. If your system boots from the remaining drive (connected in the Drive One position), this is a fairly good indication that the Disk II card and IIe are okay and that the removed drive is messed up. If it looks like a drive is bad, remove the cover and inspect the drive’s main circuit board for blown components. If nothing obvious shows up, a decent fix try is to replace the 74LS125 IC on the drive’s main circuit board. (Also, see Q&A 013.) —————————- From: Ryan Underwood I accidentally offset a row of pins on the //e disk controller card when plugging one of the drives in. Snap, crackle… you get the picture. I opened up my freshly fried Disk II, and in the center of the board there is a 74LS125 that is blown. Replaced it (it was socketed) with the same chip from another Disk II, and voila! it works again. I would assume that misaligning the drive connector on the controller is what blew the 74LS125 in se
