Re: Seeking APTEST

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

David Chiu wrote:
> Thanks for all that replied. I have two Disk II clones (Mitac) and three 
> or four half-heigh drives that won't read any disks anymore. Spindle 
> speed looks fine, heads are clean too. So I am kind of at loss as to 
> what else I can do with them.

A few questions come to mind:

1) Will the drives initialize/write new disks?  (This capability
   is unaffected by head alignment.)

2) Will the drives read disks newly initialized by the same drive?
   (This is also unaffected by head alignment.)

If they won't do 1) and 2), then there is another problem besides
alignment.

3) Will the drives do any of the above when connected to another
   controller card?   Or will another drive work with the same
   controller?  (Just to rule out a problem with the controller.)

I'm assuming (!) that the drives seek properly, meaning that they
recalibrate when attempting to boot.

I'm also assuming that each drive has its own cable, so that is
pretty much ruled out as a common source of problems.

No reading/writing can be caused by several problems, like any
discontinuity or chip failure in the read path, but the large
number of drives with the same symptoms is puzzling.  Apple
and Apple-compatible drives tend to be quite reliable unless
mis-connected.

Do these drives share some history--like being plugged into
a controller card backward or off-by-one-connector-row?  ;-(

-michael

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