mahaun@sactoh0 (Mark A. Haun) (07/12/89)
I own a 12 Mhz 286 clone (Computer Products United 286/12) with a
single 1.2 megabyte floppy drive in addition to my 20 megabyte hard
disk. Lately, the floppy drive has been malfunctioning in an odd
(and unfortunately, intermittent) way.
My problem is this: often I will try to access a disk in the
drive, and it will act exactly as if no disk were there and the
drive door was open, giving me the usual "Drive not ready -- Abort,
Retry, Fail?" message. Thinking that perhaps the problem was a
simple one (a stuck mechanical switch hooked to the drive-closing
arm, etc.), I opened up the computer, poked around a bit, and then
powered up with the case off to observe the drive working. No
matter how much I tried, I could not get it to malfunction!!! It
worked perfectly through many tests with many different disks.
Hoping the problem was gone, I put the case back on, hooked up all
my cables, and guess what... same problem!
Is there anyone (surely there must be) on the net with experience
in repairing 1.2 MB floppy drives (or anyone else, for that matter)
who could tell me what might be causing the problem and if I should
try to fix it myself or take it straight to the repair shop? This
problem is really driving me insane and I would greatly appreciate
any pointers or suggestions about what I should do. Here are some
additional facts about the problem, in case they matter:
1) The problem used to be very intermittent, and could sometimes
be cured simply by opening and closing the drive door a couple
of times. Now the drive almost never works, and when it does,
it's usually shortly after I turn it on in the morning. After
being on several hours, it *never* works!
2) Using 360K disks versus 1.2 MB disks seems to have no
significance.
3) *Everything* about the drive (it's noises, delays, etc.) is
exactly the same as if there were no disk in the drive and the
door was open. The read/write head doesn't even try to read
the disk, because it thinks there isn't one to read.
Thanks in advance for any tips or suggestions you might have...
--
( Mark A. Haun KJ6PC )( SAC-UNIX, Sacramento, CA )
( PACKET: kj6pc@wa6nwe )( UUCP: ...pacbell!sactoh0!mahaun )
( AMPRNET: kj6pc@kj6pc.ampr.org [44.2.0.56] )jwright@atanasoff.cs.iastate.edu (Jim Wright) (07/12/89)
In article <1135@sactoh0> mahaun@sactoh0 (Mark A. Haun) writes: | Thinking that perhaps the problem was a | simple one (a stuck mechanical switch hooked to the drive-closing | arm, etc.), I opened up the computer, poked around a bit, and then | powered up with the case off to observe the drive working. No | matter how much I tried, I could not get it to malfunction!!! | Hoping the problem was gone, I put the case back on, hooked up all | my cables, and guess what... same problem! | | Now the drive almost never works, and when it does, | it's usually shortly after I turn it on in the morning. After | being on several hours, it *never* works! Sounds very much like a heat problem. Another possibility is the controller card being a bit askew in the slot. But I'd bet on heat. -- Jim Wright jwright@atanasoff.cs.iastate.edu
psb@eecea.eece.ksu.edu (Phil Buckland) (07/13/89)
Sorry to have to post - my mail to you bounced. In article <1135@sactoh0> you write: >Thinking that perhaps the problem was a >simple one (a stuck mechanical switch hooked to the drive-closing >arm, etc.), I opened up the computer, poked around a bit, and then ^^^^^^^^^^^^^^^^^^^^^^ >powered up with the case off to observe the drive working. No >matter how much I tried, I could not get it to malfunction!!! It >worked perfectly through many tests with many different disks. >Hoping the problem was gone, I put the case back on, hooked up all ^^^^^^^^^^^^ >my cables, and guess what... same problem! ^^^^^^^^^^^^ I have seen problems like this when a drive cable has been pinched by the case, and where the drive cable 'bends' have been so severe as to break wires inside the cable without any external signs of damage. You might try putting the drive cable in various positions (straight or folded differently) to see if the problem stays away when the case is put back on. It is also possible for there to be a heat related problem with the drive. You don't say how long the problem took to reoccur after you put the case back on. If the problem happened immediately, it's likely not heat related. If it took a few minutes, it might be heat related. Check the power supply fan and the ventilation grills in the case to make sure that airflow is not hampered. I would play with the cables before doing this, however. >Is there anyone (surely there must be) on the net with experience >in repairing 1.2 MB floppy drives (or anyone else, for that matter) >who could tell me what might be causing the problem and if I should >try to fix it myself or take it straight to the repair shop? This >problem is really driving me insane and I would greatly appreciate >any pointers or suggestions about what I should do. Here are some >additional facts about the problem, in case they matter: > >1) The problem used to be very intermittent, and could sometimes > be cured simply by opening and closing the drive door a couple > of times. Now the drive almost never works, and when it does, > it's usually shortly after I turn it on in the morning. After > being on several hours, it *never* works! > >2) Using 360K disks versus 1.2 MB disks seems to have no > significance. > >3) *Everything* about the drive (it's noises, delays, etc.) is > exactly the same as if there were no disk in the drive and the > door was open. The read/write head doesn't even try to read > the disk, because it thinks there isn't one to read. Thanks for the extra info. - it rules out a few possibilities. You might also check the drive cable to see if it is routed close to a heat source (see if the cable is warm and where). If a bend in the cable is present near the heat source, brokes wires in the cable could expand from the heat and provide poor contact. Try rerouting/rebending the cable. If the problems go away, it's probably worth replacing the cable. >Thanks in advance for any tips or suggestions you might have... > >-- >( Mark A. Haun KJ6PC )( SAC-UNIX, Sacramento, CA ) >( PACKET: kj6pc@wa6nwe )( UUCP: ...pacbell!sactoh0!mahaun ) >( AMPRNET: kj6pc@kj6pc.ampr.org [44.2.0.56] ) Phil Buckland Computer Engineer psb@eecea.UUCP psb@eecea.eece.ksu.edu