Re: 5.25 Speed Problems

[Rubywand <rubywand@swbell.net>]

william strutts writes ...
> 
> I have tried several different DDDS diskettes.
> 
 ....

     Has this drive ever worked for you?

     You mentioned cleaning the drive; did you used a "head cleaner disk"--
i.e. a paper diskette you squirt some alcohol on? If you did, was the bottom
(down-facing, Side 2) access flap removed?  (On 5.25" Apple II drives, the
R/W head is on the bottom.)

     When cleaning A2 5.25" drives with a "head cleaner disk", the top access
flap should be in place to avoid wear on the pressure pad.

     It may be a good idea to visually inspect the head to make sure it's not
gunked up.


     Wonder if the problem could be that your speed adjustment is so far off
that it is beyond the range of the Copy II+ speed check. (So, the program
flipflops and gives eratic outputs.)

     With everything OFF, try to set the drive's speed adjustment somewhere
roughly near the middle of its range. (Like, if it's a 10-turn pot, go to one
end and then do 5 turns the other way.)

     Boot Copy II+ and try doing the speed check again. This time, make small
adjustments and wait a second or two between each to see if you get a stable
reading. Once you get some stable reading, adjust to "200".

     If you can not get a reasonably stable 200 reading-- one which stays
within 198 and 202, try gently wiggling the drive cable near each end with
the test running. If a wiggle helps, you may have a broken line in the drive
cable or dirty connection on one end or the other.

     Another try is, with everything OFF, to scootch up and resocket each
socketted IC on the Drive Controller card and (if there are any) on the disk
drive circuit board. Also, unplug and replug the drive cable on each end.

 

Rubywand