Re: Apple ][ plus 13 sector! Problems...

[mjmahon@aol.com (Michael J. Mahon)]

Richard Kilpatrick wrote:

>On 19/7/04 8:00 pm, in article 20040719150048.04872.00000141@mb-m12.aol.com,
>"Michael J. Mahon" <mjmahon@aol.com> wrote:
>
>> 
>> From what you have described, it is very unlikely that there is anything
>> wrong with your 13-sector controller card.
>> 
>> Think drive (dirty heads, speed wrong, with any luck) or disk.
>
>The speed adjustment appears to have very little effect - would I notice any
>variation without test equipment? I've tried several disks, so either they
>have been stored in a loudspeaker (possible), or I can (hopefully) eliminate
>them.

If you have the drive out of its case, then turn it upside down and look
at the hub pulley.  There should be two stroboscope tracks, one for 50Hz
(more "stripes") and one for 60Hz (fewer "stripes").  Using a flourescent
light (or a non-halogen tungsten light in a pinch), adjust the speed pot
to make the correct stobe ring stop rotating.  The speed is now correct.

>Cleaned the heads. Well, put cleaner on a Q-tip and gently swapped. No sign
>of any dirt :/

Sounds good.

>Richard (cleaning the contacts and 'fiddling' resulting in instead of a
>crash to Monitor, getting an IO ERROR or just ERR a couple of times, but no
>consistency).

The behavior you describe points to the disk(s) being faulty, though
the drive is not yet ruled out.

-michael

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