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joesmith joesmith is offline
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Default Viewsonic VG150 logic board 0171-2242-0153 3150-0122-0150 repairhelp

On Dec 15, 1:16*am, Boyan wrote:
I have Viewsonic VG150

Problem with the logic board marked as 0171-2242-0153 and
3150-0122-0150 by means of silk screen on green PCB, looks original by
the fab house. Also E11131070 is printed on a white sticky label,
affixed at a later time.

The issue is that my VGA image is fuzzy, with white horizontal lines
from top to bottom. You can still see the payload image behind the
white horizontal lines. The lines seem pretty stable with just slight

Using deductive logic, I condicted more tests and observed that the
built-in menus (generated internally) for contrast, monitor info, etc
are perfect. No lines at all. The lines show up only when VGA signal
is present.

So I deduced the issue is on the analog part, close to the signal
connector - bad pre-amp, bad gate, etc.

Not having schematic I figured the first hit is the Mitsubishi
M52743BSP chip. Ok swapped it out (yay $5 at Newark) but my lines are
still there and my built-in menus are clear and stable.

I see few AmTran ICs, some a good suspect but I though I should
increase my IQ approach in troubleshooting this issue.

Any help?


Replace ALL the caps in the power supply,,little
black box,been there :done that; many, many, times.
West Point Monitor Repair
West Point, Texas