Electric & Vm Focus Adjustment, Complete Adjustment; Rear View - Panasonic P7W Service Manual

2. Set VIDEO C_OFF DAC from 00 to 02, and project
only red. Adjust red focus VR so that focus is best..
+ + +
R G
+ +
R G
Figure 28. Focus pack
3. Adjust red lens focus (mechanical) until focus is
best.
4. Adjust red focus VR again.
5. Set VIDEO C_OFF DAC from 00 to 01, and project
only green.
6. Repeat steps for green only.
7. Set VIDEO C_OFF DAC from 00 to 03, and project
only blue.
8. Repeat steps for blue only.
Focus - Optical lens adjustment
Optical adjustments
Note: This adjustment normally should not require
resetting unless the lens has been replaced or
adjustment has changed.
1. Optical focus adjustment is located on the top of
each CRT lens system. Loosen the adjustment
knurled locking knob. (figure 29)
Adjustment knurled
locking knobs
B G

REAR VIEW

Figure 29. Optical lens focus adjustment
2. Turn the PTV ON. Apply and view a crosshatch
with dots pattern.
3. Adjust each lens focus for best focus while viewing
each CRT.
4. Cover the red and blue CRT, projecting green only.
Rotate the green lens for best focus around screen
center area.
5. Do the same for the red focus lens while projecting
red only.
6. Repeat for blue.
Service Manual
screen
B
focus
B
R
Electric & VM focus adjustment, complete
adjustment
(Perform this adjustment when a CRT is replaced
or when major adjustment is required)
Preparation:
1. Apply a NTSC crosshatch pattern with dots.
2. Set CONV "MUTE" DAC from 0 to 1 (disabling
digital convergence.)
3. Position the longer tab of the four-pole magnet to
90 degrees (uncorrected position). (see figure 31).
Figure 30. VM coil with focus
correction magnet
Figure 31. 4-pole magnet
4. Position the long tab of all alignment magnets and
of the dummy ring together in an uncorrected
position. (See figure 32).
Figure 32. Alignment magnet
(or dummy ring)
Procedure:
1. Apply an NTSC cross hatch pattern with dots.
2. Assure that digital convergence is disabled (DAC
MUTE from 0 to 1).
3. Set VIDEO "C_OFF" DAC from 00 to 02, to project
red only.
4. Turn the red electrical focus adjustment VR (on
focus pack) fully counterclockwise and note the
position of the dots at the center of the picture.
5. Turn the red electrical focus adjustment VR
fully clockwise.
- 24 -
6-pole magnet
(Dummy ring)
4-pole magnet
Alignment magnet
Set 90 degrees