jeffj@pedsga.UUCP (09/26/88)
[spritzensparken!] I have had two Tandon TM-848-02 floppy drives fail recently. (half height DSDD 8") Both failed the same way. They worked as double sided, then the upper head failed. Now they cannot read nor write the upper side, but function okay as single sided. The heads look fine. What went wrong? Can I fix it easily and cheaply? (Remember that new drives are $50 at computer fairs). Thanks for your assistance. Jeffrey Jonas allegra!io!mtune!petsd!pedsga!jeffj decvax!mcnc!rutgers!petsd!pedsga!jeffj
commgrp@silver.bacs.indiana.edu (09/29/88)
>I have had two Tandon TM-848-02 floppy drives fail recently. (half >height DSDD 8") Both failed the same way. They worked as double sided, >then the upper head failed. Now they cannot read nor write the upper >side, but function okay as single sided. >The heads look fine. What went wrong? Can I fix it easily and >cheaply? (Remember that new drives are $50 at computer fairs). > >Jeffrey Jonas Upper head failure is common on all floppy drives. Unlike the lower head, the upper head is mounted on a delicate suspension. Sometimes they fail for no apparent reason; the most common failure mode is the upper head being torn away because someone put a disk with a warped jacket into the drive, or because a technogeek interpreted the message "Put a write-protect tab _ON_ the disk" literally. :^( It's not economical to replace the heads; new heads cost almost as much as a whole new drive, and a good bit of labor is involved in realigning a new head, even if you have all the right equipment (test set, analog alignment disk, oscilloscope). I have been able to salvage a few drives with bad upper heads: Carefully inspect the solder joints where the cable connects to the flat flexible printed-circuit leading to the actual head. The wires often break here, and the break may not be obvious until you disturb the wire. Broken wires can be resoldered, using a very small tip. -- Frank reid@gold.bacs.indiana.edu