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			<title>Macintosh Plus: SCSI Hard Drive Recognition Problem</title><body class="ac-gn-current-support">
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<h1 id="main-title">Macintosh Plus: SCSI Hard Drive Recognition Problem</h1>
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<div id="intro-container"><div class="truncate"><div class="attr SYMPTOMS"><div class="attr TOPIC"><FONT SIZE=4><BR>
<BR>
I have a Macintosh Plus, with an external SCSI hard drive that has worked<BR>
reliably for over a year.  Suddenly the Macintosh won't recognize the<BR>
drive, though both the Macintosh Plus and hard drive work fine separately<BR>
(for example, using the hard drive with a Macintosh SE).<BR>
<BR>
</FONT></div></div> <!--  attr Symptom  --></div> <!--  truncate --></div> <!--  intro-container --><div class="clear"> </div>
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  <div class="attr SUMMARY">
Most probably something has blown the IC on the hard drive's analog board<BR>
that controls the SCSI reset line.  Since the Macintosh Plus (and the<BR>
Macintosh Portable) doesn't have SCSI termination power, this problem can<BR>
only be fixed by replacing the hard drive assembly.<BR>
<BR></div>
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<div class="mod-date">Published Date: Feb 18, 2012</div>
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