Re: Problems! Disk ][ drive just whirs and whirs; IIc monitor knob stuck; IIe enhanced not...

["Michael J. Mahon" <mjmahon@aol.com>]

Larry Stedman wrote:
> Appreciate the fast responses!  Thanks for the //e, 80 col. card history.
>
> Is there any possibility that a chip was pulled or that something needs 
> to be re-seated on the motherboard to restore it to being a //e?   I 
> guess I should Google and see what the enhanced motherboard looks like.  
> Oh, wait, one of the IIes here is an enhanced.  I'll open 'em and 
> compare.
>
> How would I go about cleaning the disk drives?  I know in the old days 
> Radio Shack sold disk drive cleaning kits, but I can't believe they'd 
> have anything like that anymore!  
>
> I'm tentatively ruling out the cable as both Disk ][ drives have the 
> same problem so it'd have to be a prob with each of their cables!  
>
> Does that Track $11, Sector $F  i/o error mean something?  I don't get 
> the initial rattling that most Apple II drives give you when they're  
> trying to read a disk.  Head issue?  Stepper motor prob?  
>
> Could a disk ][ controller card problem prevent a disk from 
> reading/working properly?  That would affect both of them.

If you have some spare ICs, try replacing the 74LS259 on the
controller card.  It directly drives the four "phase" lines
that control the head stepper, so ESD or bad plugging juju
could fry it, resulting in no seek.

-michael

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