Philips 202P4, Service Manual

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General Troubleshooting Guide
202P4 M25P
END
Focus
YES
During normal viewing conditions of a monitor, Focus at center of the screen should be sharper
than the edges of the screen. However, focus on the edges should still display legibly at the
Philips recommended resolution and refresh rate for all Philips monitor sizes.
Set brightness and
contrast to appropriate
viewing level.
Are brightness
and contrast
too high ? Does monitor have
a Focus control ?
Adjust Focus
Focus problem resolved ?
Incorrect resolution/
refresh rate for
monitor size ?
Use video utilities
to set proper
resolution and
refresh rate for
monitor size.
Does it cause by
convergence
alignment ?
Case study : P-Line Focus issue (107P10/20, 109P10/20, 201P10)
Symptom: Poor Focus, Blurry Picture, colored outlines around characters.
Possible Cause:
Convergence Issues:
What is Convergence : As we know the CRT is comprised of thousands of color phosphor dots, (red, Green, and Blue).
Convergence is the alignment to ensure that the proper electron beam strikes the correct colored phosphor dot
and the correct triad of phosphor dots. (Triad = a group of each colored phosphor dots forming a triangle / Bold below)
For a better photo refer to any of our CD ROM's under glossary of terms and Dot Pitch.
R G B R G B R G B
B R G B R G B R
R G B R G B R G B
Convergence is typically not adjustable by the customer.
On the P-Line with a Diamondtron CRT, Convergence can be found in the main menu under extra controls.
If convergence is misadjusted, it will appear out of focus to the untrained eye.
Looking closely may reveal that characters will have a colored outline around them. (Red, Green or Blue.), if so..
It is not a focus issue but a convergence alignment problem.
Cure: Using the On Screen Display of the monitor, adjust the Horz and Vert Convergence under extra controls in the menu.
Using the On Screen Display
of the monitor, adjust the
Horz and Vert Convergence
under extra controls in the
menu.
For example :
107P10/20, 109P10/20
, 201P10/20
NO NO
NO
NO
NO
It is need to check and
repair the monitor.
Is it acceptable ? YES
NO
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