[comp.sys.atari.st] SM124 Monitor Problem

bright@ccu.umanitoba.ca (Bob Bright) (01/17/91)

I've got a problem with my SM124 monochrome monitor.  A few months ago
I started to loose the left-hand edge of the display -- i.e.
characters in the first column of the display were squished into about
half their normal width.  The problem has gotten progressively worse,
until the point where I can just barely read characters in the second
column (the first column has pretty much disappeared entirely).
Fortunately I use mostly GEM applications, so I can move the window to
the right in order to keep things readable, but if the problem gets
much worse I'm going to find myself back in the days of 40-column
displays.

I'm sure the problem resides in the monitor, since connecting it to my
wife's 520ST doesn't help.  The monitor is about 3 years old, and has
seen very heavy use.  Does anyone know:
     (i) what's causing the problem?
    (ii) how to fix it, short of buying a new monitor?

Thanks alot for any advice, BBB
-- 
Bob Bright <bright@ccu.umanitoba.ca>
Dept. of Philosophy
University of Manitoba
Winnipeg, Man  R3T 2N2  (204) 474-9680

smisra@eos.ncsu.edu (SAURABH MISRA) (02/23/91)

I suddenly started getting problems with my well kept
monochrome monitor...for some reason the monitor just
turned off by itself...since the symptoms were very
indicative of a blown fuse (that is absolutely no power
anywhere) I opened up the case and replaced it again
with the same volt and ampere fuse and then it blew again
What is going on?  Please let me know if you know how to
fix this problem,

thanks
Saurabh

neil@cs.hw.ac.uk (Neil Forsyth) (02/27/91)

In article <1991Feb23.151137.12800@ncsu.edu> smisra@eos.ncsu.edu
(SAURABH MISRA) writes:
]I suddenly started getting problems with my well kept
]monochrome monitor...for some reason the monitor just
]turned off by itself...since the symptoms were very
]indicative of a blown fuse (that is absolutely no power
]anywhere) I opened up the case and replaced it again
]with the same volt and ampere fuse and then it blew again
]What is going on?  Please let me know if you know how to
]fix this problem,

Well I reckon a bridge rectifier diode in the power supply might be a good
guess. They've gone short circuit here a couple of times causing the fuse to
blow. I think the part number is IN5402. Hopefully that's all that's wrong.

]thanks
]Saurabh

Your welcome.

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