Chapter 4—Setup Adjustments
4-22 Hughes-JVC Technology Corporation
CRT Focus and H/V Dynamic Focus). This factory-setting does not
normally require readjustment. The FOCUS ENABLE box in the
PREFERENCES MENU may now be unchecked to prevent accidental
defocusing.
4.4. CRT Focus and H/V Dynamic Focus
The CRT and H/V Focus adjustments are factory-set and do not normally require
adjustment. They should be performed together in a back-and-forth manner to
achieve the best possible overall focus.
To perform the CRT Focus:
1. From the FACTORY ADJUSTMENTS MENU, select CRT FOCUS.
2. Select G on the remote.
3. Select the STANDARD CROSSHATCH test pattern.
4. Use the up/down arrow keys to obtain the best possible f ocus in bot h the
center of the screen and in the overall test pattern.
5. Repeat the above steps for R and B.
To perform the H/V Dynamic Focus:
1. From the FACTORY ADJUSTMENTS MENU, select H/V DYNAMIC FOCUS.
2. Continue with the STANDARD CROSSHATCH test pattern from above.
NOTE: The H/V Dynamic focus is performed on all three (3) colors together
and the colors are not individually selectable.
3. Use the up/down arrow keys to achieve the best possible focus at the edg es
of the screen.
4. Repeat the CRT Focusing f rom above, then repeat the H/V Dynamic Focus
again. Several iterations may be needed to achieve the best possible overall
screen focus.
4.5. ILA® Sensitivity and Bias
ILA® Sensitivity and Bias are preset for the factory-set sources and will not
normally require adjustment. Readjustments may be required due to variations
between the factory and the field environments. When new sources are set up,
ILA® Sensitivity and Bias must be set (or copied from another source and
touched-up) for each new source.
The ILA® Sensitivity and Bias can be adjusted for any color. It is preferable to
start with Blue since Blue is a weaker color to observe than Red or Green. The
ILA® Sensitivity is the ILA® biasing frequency that affects the resolution and
brightness on the screen. The ILA® bias settings adjust the electrical bias levels
to each ILA® assembly to a ���just off” threshold point. The smallest incoming light
from the CRT will cause the ILA® assembly to react. When properly set, this
adjustment will put each ILA® assembly at the threshold of operation. If set
incorrectly, the black level will be adversely affected and the ILA® assembly will
not react properly to incoming light. Perform all ILA® Bias adjustments in a
darkened room.