On 2016-06-27 06:54, J.B. Wood  wrote:

> On 06/25/2016 07:30 PM, B00ze wrote:
>> On 2016-06-25 03:49, frank  wrote:
>>
>>> I downloaded the fine commodore 1541 troubleshooting and repair guide
>>> and
>>> it has procedures based on the "Dysan Analog Alignmnet diskette 224/2A".
>>> Now I guess this one is next to impossible to get nowadays, right?
>>
>> Vorpal, if I recall, also came with an alignment disk - I used to have
>> one. The problem is that you can't copy this disk, because then the disk
>> acquires the alignment of the drive that wrote it (but if you copy it on
>> a perfect drive then you're good).
>>
>> This guy had some for sale last year:
>> http://www.lemon64.com/forum/viewtopic.php?t=55340
>>
>> Regards,
>>
> Hello, and I've still got two operating 1541s with the original long
> circuit boards.  (Still amazed that the drive belts never required
> replacement after 30 years.)  The only thing (other than alignment) that
> ever went wrong was that I had to replace a failed voltage regulator in
> one of them but that was a long time ago).

You mean those things near the back, with the heat sinks? Yop, had one
of those die on me too.

> As for alignment, the original factory procedure required a special disk
> and an oscilloscope.  I have a package, "1541 Physical Exam" by Cardinal
> Software that also has a special disk but you can do a complete
> alignment just using the info displayed on the monitor.  This package
> also included two bent piano wire track 1 stops to replace the original
> solid metal ones that were responsible for most 1541 drive alignment
> problems.  A lesser problem was when the spindle was not turning at the
> required 300 rpm.  Sincerely,

The Vorpal tool reads the alignment disk (it moves the head back and
forth over about 2 tracks, constantly) and reports an alignment number.
You can then unscrew the 2 screws holding the step motor and rotate it
slightly in one direction or the other. Screw it back and repeat the
test. It's coarse but it works, I did it several times (you can tell
you're ok when other people can read your disks again). The problem is
you'd need to use glue on those screws once you've played with them,
otherwise alignment drifts over time (unless you are able to screw those
screws really really tight).

Regards,

--
! _\|/_  Sylvain / B00ze64@hotmail.com
! (o o)   Member:David-Suzuki-Fdn/EFF/Red+Cross/SPCA/Planetary-Society
oO-( )-Oo  "Captain ... one ... harmless ... little ... Tribble?"

--- SoupGate-Win32 v1.05