nms@homxc.UUCP (N.SCRIBNER) (12/17/86)
What is the latest scoop on alignment of old 1541 dis drives? Is is cost effective to take it to the local fixit shop? Send it to Commodore? Buy a kit? Is there public domain SW which would allow an "educated", (but not expert) user to align a unit himself. Thanks for the advice. Neal Scribner ATT-BL 201-949-2242 homxc!nms
dickow@ui3.UUCP (12/20/86)
/ ui3:comp.sys.cbm / nms@homxc.UUCP (N.SCRIBNER) / 10:31 am Dec 17, 1986 /
What is the latest scoop on alignment of old 1541 dis drives?
Is is cost effective to take it to the local fixit shop? Send it to
Commodore? Buy a kit? Is there public domain SW which would allow
an "educated", (but not expert) user to align a unit himself.
Thanks for the advice.
Neal Scribner
ATT-BL 201-949-2242
homxc!nms
----------
1541 drives, especially 'older' ones, go out of alignment so frequently
that it seems cheaper to buy a new one sometimes. However, I have been align-
ing my own for some time. I use the CSM alignment program. Skyles electric
works is also selling a program at about 29 bucks. You can find ads for these
in just about any issue of COMPUTE! or RUN mag. I'd supply addresses but I
loaned my disk to a friend. The program comes with an extra special alignment
standard disk, so you can't pirate the thing. If you can handle a screwdriver
you can do the job. Just watch out for the 110 volts, and be careful not to
accidentally 'strip' the phillips heads that hold down the stepper motor.
Just one alignment performed yourself will pay for the program, since
shop jobs will cost anywhere from 30 to 79 bucks. The CSM program ran me about
$45. The first time you do it the job is a little frustrating...takes about
an hour to get it right, and some 'hunting and pecking' for the best adjust-
ments is necessary.
Bob Dickow, Univ. of Idaho School of Music
egg-id!ui3!dickow
idwl10@amdahl.UUCP (Dave Lowrey) (12/22/86)
SAMS publishes a technical manual on the 154[0,1,2] disk drives.
In the manual are two techniques for alligning the drive. One requires
a scope, and the oyther requires a DVM. I use the DVM method to allign
my drive, and it seems to work well.
Also included is a strobe wheel, that yoyu can xerox and attach to the
motor's flywheel. Hold it under a flourescent light, and you can adjust
the motor's speed.
I got my manual at Walden Books.
--
-------------------------------------------------------------------
Dave Lowrey
"So it goes, so it goes, so it goes, so it goes. But where it's
going, nobody knows" [Nick Lowe]
...!{ihnp4,cbosgd,hplabs}!amdahl!dwl10
[ The opinions expressed <may> be those of the author and not necessarily
those of his most eminent employer. ]lishka@uwslh.UUCP (Christopher Lishka) (12/23/86)
In article <60006@ui3.UUCP> dickow@ui3.UUCP writes: >/ ui3:comp.sys.cbm / nms@homxc.UUCP (N.SCRIBNER) / 10:31 am Dec 17, 1986 / > >What is the latest scoop on alignment of old 1541 dis drives? >Is is cost effective to take it to the local fixit shop? Send it to >Commodore? Buy a kit? Is there public domain SW which would allow >an "educated", (but not expert) user to align a unit himself. >Thanks for the advice. > >Neal Scribner >ATT-BL 201-949-2242 >homxc!nms >---------- Ahhh, yes...I used to have a lot alignment problems too. However, the second time my drive went out of alignment, the repairman I took it to performed what he called a 'permanent' modification, and swore that the heads would never go out of alignment again. Alas, he was correct...I haven't had ANY head alignment problems with my drive for about three and a half years now. From what I understand, the older drives had two metal components 'pressed' together, held in place only by friction. I guess that these two components controlled some aspect of head movement. I've looked inside my drive at what the repairman did, and it seemed he drilled a hole where these two metal pieces meet and then drove a good-sized screw into the whole. This keeps the two metal pieces from slipping. The repairman told me that this modification was fairly common...the best part about it, though, was that it cost the same price as a head alignment ($22.50 for half-an-hour's work). Now, the store I had it done at has gone out of business since the repair nearly four years ago...however, I think that it would probably be worth your while to get this done (by someone who knows what they are doing), because it can save a HELL of a lot in alignment fees. Also, you don't have to worry about writing to disks when the heads are 'slightly' out of alignment, insuring that you cannot read from those disks when your heads are back into alignment (this has happened to me more than once, BEFORE I had the permanent modification). -- Chris Lishka /lishka@uwslh.uucp Wisconsin State Lab of Hygiene <-lishka%uwslh.uucp@rsch.wisc.edu \{seismo, harvard,topaz,...}!uwvax!uwslh!lishka
wtm@neoucom.UUCP (Bill Mayhew) (12/24/86)
Hi, There is a steel band that moves the head carriage back and forth in a 1541 disk drive. The band is attached to a small pulley on the shaft of a stepper motor located near the rear of the drive. On the older dirves (I don't know about the newer ones), the pulley was pressed on the shaft and NOT secured by set screws or the like. One or more commonly available books contian descriptions on how to drill a hole through the pulley and shaft, then insert a pin to prevent the pulley from slipping on the shaft. The usual problem that causes misalignment is stupid software (usually copy-proofed) that forgets how many tracks it has moved the head and keeps trying to turn the stepper motor, eventhough the head is upagainst the stop after track 35. In one case the pirating (er... backing up) program, Disector, tried to step to track 36 on my Parent's machine, thus causing a minor alignment gaffe. I think that the book, _Inside the 1541 DOS_, is one that contains the information on how to realign your drive. It has a short basic program for the purpose. It is possible to do so without special tools, as the c64 itself can tell you if it is reading the diskette correctly. It will take patience though, as it is an iterative process to get the alignment correct. You'll also need to have a diskette that was formatted on a machine whose alignment you trust (or at least you want to be compatible with). If you don't feel pretty self-confident and know at least a little about how a drive works, it is probably best to let a shop do the job for you, as $39-49 is a lot less than ~$200 if you screw up your drive. If anybody is worried about the exact title of the book, send me an email, and I'll get it for you. It's readily available since I got a copy at Walden Books. --Bill Bill Mayhew Division of Basic Medical Sciences Northeastern Ohio Universities' College of Medicine Rootstown (really!), OH 44272 USA phone: 216-325-2511 (wtm@neoucom.UUCP ...!cbatt!neoucom!wtm) By the way, Happy Holidays (nondenominational message).