Path: utzoo!attcan!uunet!lll-winken!lll-tis!ames!ll-xn!mit-eddie!uw-beaver!tektronix!reed!kamath
From: kamath@reed.UUCP (Sean Kamath)
Newsgroups: comp.sys.apple
Subject: Re: Fix for disk drives
Message-ID: <9799@reed.UUCP>
Date: 13 Jul 88 05:26:19 GMT
References: <157@thelink.UUCP> <10863@andante.UUCP>
Reply-To: kamath@reed.UUCP (Sean Kamath)
Organization: Reed College, Portland OR
Lines: 21

In article <10863@andante.UUCP> jac@forte.UUCP (Jonathan Chandross) writes:
>R. Allen "Urt" Wilkinson (urt@cmr.icst.nbs.gov) Writes:
>This is a very common problem with an uncommonly simple solution.  The 74125
>on the logic board in the drive has burned out.  This causes the drive to
>write garbage all over your disk, whether or not it is write protected (look
>at the schematic -- it's after the write enable/disable circuitry).  All you 
>have to do is buy a new 74125 (less than a dollar) and install it.  
>
>Jonathan A. Chandross

I do know that Apple has an authorized fix for DuoDisks.  Seems they need to
either change/replace/remove a capacitor on the analog card on those babies.
I'd check and make sure you have a "good" one.  I might be able to get
serial numbers, but it should be easy enough through your local dealer. I'm
not sure but I recall the stated symptoms match.

Sean Kamath
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