Path: news.uiowa.edu!news.physics.uiowa.edu!math.ohio-state.edu!cs.utexas.edu!swrinde!news.sgi.com!news.msfc.nasa.gov!newsfeed.internetmci.com!news.mathworks.com!nntp.primenet.com!ddsw1!news.mcs.net!van-bc!ts209.vcr.wis.net!user From: dmanzer@wimsey.com (War Lib'y Canada) Newsgroups: comp.sys.apple2 Subject: Re: Malfunctioning 5.25" drive: please assist Date: Sun, 01 Sep 1996 22:49:04 -0800 Organization: Canadian War Library Lines: 27 Message-ID: References: <50cup5$i12@zot.io.org> NNTP-Posting-Host: ts209.vcr.wis.net In article <50cup5$i12@zot.io.org>, crownmi@zot.io.org (Myles Fudge) wrote: > It seems that the malfunctioning > drive is damaging the disk. The symptoms you describe are the usual result of having removed the disk controller card while power is on, which shorts 12vdc across a 5v line, blowing the LS125 on the disk analog board. To repair it: * Turn power off! * Remove the cover of the disk drive * Replace the 74LS125 in the circuit board on top (make sure to observe where pin 1 of the chip is; look for the notch at the end) * Reassemble and try with a disk formatted in the working machine. Good luck! Regards, Doug Manzer