Path: utzoo!mnetor!uunet!husc6!hao!ames!ucbcad!ucbvax!RADC-TOPS20.ARPA!GUBBINS
From: GUBBINS@RADC-TOPS20.ARPA (Gern)
Newsgroups: comp.sys.zenith.z100
Subject: Re: floppy controller prob
Message-ID: <12357407757.13.GUBBINS@RADC-TOPS20.ARPA>
Date: 10 Dec 87 18:28:12 GMT
References: <8712101853.AA06460@ll-vlsi.arpa>
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The ARPA Internet
Lines: 16

Hmmm.   I have had even worst problems than that at one time testing
controllers and damaging drives which damaged my good controller, etc...

Start from scratch and see if your 'was-good' controller had any of
the pots on the upper left moved (breaking the gliptal orange seal).
Then push around and reseat all the ICs.  Check the transistors and
other components for lead breaks (This may happen during rough removal
and hitting cables).  If this all fails, I'd say you took a static
damage hit (This is the season).  It probably is one of the 3 Western
Digital Chips (50% chance), try trading them with your friends controller.
The Floppy Controller is repairable if you have a known good chip set
and some time.   I've done it, and the victim had 2 bad ICs...

Cheers,
Gern
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