Path: utzoo!attcan!uunet!samsung!aplcen!unmvax!ogccse!blake!milton!uw-beaver!uw-june!gordon
From: gordon@cs.washington.edu (Gordon Davisson)
Newsgroups: comp.sys.mac.hardware
Subject: Re: Mac Plus Video Problem - a cause
Message-ID: <9847@june.cs.washington.edu>
Date: 17 Nov 89 08:54:24 GMT
References: <1989Nov14.134706.7858@uncecs.edu> <36480@apple.Apple.COM>
Reply-To: gordon@june.cs.washington.edu.cs.washington.edu (Gordon Davisson)
Organization: University of Washington, Computer Science, Seattle
Lines: 23

>In article <1989Nov14.134706.7858@uncecs.edu> hunnic@uncecs.edu (Jeff Hunnicutt) writes:
>>I have a Mac Plus that exhibits the symptom of a single vertical
>>line up the middle of the screen. My question is this, does anyone 
>>know what particular component may be failing?

In article <36480@apple.Apple.COM> baum@apple.UUCP (Allen Baum) writes:
>I've been informed that the usual cause for that problem is the failure of
>a 3.9uf 25v non-polarized capacitor. Its about 1.25" high, .5" diameter,
>near the top of the board, component number C1.

C1 failure generally won't collapse the display all the way down to a
single line.  The problem is more likely to be a bad solder joint on
the yoke connector; it's the 4-pin connector near the top front of the
analog board, right underneath one of the foam tape pads that hold on
the insulating sheet.  A bad connection on either of the top two pins
will cause the described symptoms, though the top one almost always goes
first.  (Actually, it's a good idea to resolder all four pins; they'll
all go eventually)

--
Gordon Davisson
Westwind Computing	(206) 632-8141
4518 University Way NE, Suite 313, Seattle WA 98105