RX02 Problem solved...

[Allison]

>
>Subject: RX02 Problem solved...
>   From: Gary E Kaufman <gkaufman at the-planet.org>
>   Date: Tue, 26 Sep 2006 22:10:26 -0400
>     To: cctalk at classiccmp.org
>
>Tony and others -
>
>The head load pad looks visually fine.  The head load spring tension 
>appears pretty normal , and the solenoid pulls in nicely.
>
>The drive consistently reads the first 10 or so tracks, then tosses 
>various number of errors as it goes further out.
>
>I've cleaned the head, and cleaned/lubed the spindle.  The track 0 
>sensor appears fine.

Also make sure the rails the head travels on are clean.  The whole 
mess should move very smoothly.

>It is indeed possible that the alignment is off - that would probably 
>explain the poor performance as it steps out.

If it's bad on the outer tracks then it will be bad elsewhere. The only 
way it can get worse is if the lead screw or the follower is worn to the 
point of looseness.

>I guess a worn out head would have the same symptoms. 

That can be visually inspected under a magnifier.  Never seen that happen.

> I the 70's I had a neat Dysan digital alignment disk that I used to 
>realign a few SA901 and SA801 drives.
>Unfortunately I no longer have it.  I suppose I could mark the position 
>of the stepper and slightly rotate it in each direction to see if it 
>improves things. 

Shugart made one too.

>
>If someone can point me to an actual alignment procedure I'm game - I 
>have reasonable scopes etc here.

Without the disk or a known good disk you not going to get the best results.


Allison