Crt Electronic Focus - Hughes JVC 100 Service Manual

4. Put on safety gloves (see Safety section for gloves type) and loosen the 2
Phillips screws on the Green ILA
being focused) (see Figure 3-7).
5. Manually position the Front Lens Focus Adjust at the mid position. Grasp
the end of the Front Projection Lens and turn until the Adjustment Pin in
the Adjustment Slot is at midpoint (see Figure 3-8).
6. Stick a flat-blade screwdriver in the adjustment slot and move the ILA
Assembly back and forth until the spacer balls are in focus (see Figure 3-7).
7. Tighten the 2 Phillips-head screws (see Figure 3-7) on the Green ILA
Assembly base.
8. Repeat Steps 4-6 above for other Red and Blue Channels as need. Be sure
to hide the other 2 colors.

3.4 CRT Electronic Focus

The CRT Electronic Focus is factory-set and will not normally need to be adjusted
except after component replacement, maintenance, or if wide temperature
variations exist between the factory and the field location. View one color at a
time.
1. Select the Test Pattern #6 (the Focus test pattern).
2. Attach a non-interlaced source, approximately 31.5 kHz X 60 Hz (this
makes it easier to see the raster lines).
3. Maximize the size on all three colors.
4. Hide the channels that are not being adjusted.
5. Zoom the Projection Lens to the widest angle and adjust the Projection
Lens focus for the sharpest image (ensure Spacerballs are properly
focused).
Model 100 Service Manual
Figure 3-8 Front Projection Lens Adjust
Chapter 3---Service Adjustments
®
Assembly base (or whichever channel is
Adjustment
Adjustment
pin
®
®
Slot
3-11