Newsgroups: comp.sys.3b1
Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!think.com!zaphod.mps.ohio-state.edu!n8emr!colnet!res
From: res@colnet.uucp (Rob Stampfli)
Subject: Re: (*SIGH*) 3b1 monitor question.
Message-ID: <1991May18.161722.21388@colnet.uucp>
Organization: Little to None
References: <1991May17.194725.29834@digibd.com>
Date: Sat, 18 May 1991 16:17:22 GMT

The most common problem with 3B1 monitors is a failure mode where the right
side of the screen becomes increasingly nonlinear.  Once this starts, it
proceeds at an exponential rate until the monitor fails.  The problem is
a bad capacitor in the flyback circuitry.  If it is caught prior to the
actual failure of the monitor, this is all that has to be replaced.  Once
the capacitor fails, it takes out many hard-to-replace parts, like the
flyback transformer, effectively rendering the monitor unrepairable at any
reasonable cost.

The +12V is used to power the DC fan and certain signals on RS232 ports.
It is also used by the disks (hard and floppy) and monitor.
-- 
Rob Stampfli, 614-864-9377, res@kd8wk.uucp (osu-cis!kd8wk!res), kd8wk@n8jyv.oh