Table of Contents
Advertisement
Initial center static convergence
Connect a dot/cross hatch generator to the receiver
and tune in a signal. Observe misconvergence at
center of the screen only.
Adjust the R&B pole magnets; by separating tabs and
rotating to converge blue with red.
Adjust the R&B and R&B&G pole magnets: by
separating tabs and rotating to converge blue and red
(magenta) with green.
Note: Precise convergence adjustment at this point
is not important.
Purity adjustment
When the receiver is in the service mode for making
electronic adjustments, press the RECALL button on
the remote control to enter purity check. (See the
service adjustments electronic controls procedure).
Operate the receiver for 60 minutes using the first
purity check field (white screen) to stabilize the CRT.
Fully degauss the receiver by using an external
degaussing coil.
Press the RECALL button on the remote control again
until the purity check (green screen) appears.
Loosen the deflection yoke clamp screw and move the
deflection yoke back as close to the purity magnet
as possible.
Adjust the purity rings to set the vertical green raster
precisely at the center of the screen (see Fig. 12).
NOTES:
1. CRT warm up with white screen
(three guns activated) is needed
to stabilize the shadow mask
expansion.
2. Initial center static convergence
(roughly
centers
three
beams) is required in order to
perform purity adjustment.
Figure 12. Green raster adjustment
Slowly move the deflection yoke forward until the best
overall green screen is displayed.
Tighten the deflection yoke clamp screw.
Press the RECALL button on the remote control again
until the purity check blue and red screens appear and
observe that good purity is obtained on each respective
field.
Press the RECALL button on the remote control again
until purity check (white screen) appears. Observe the
screen for uniform white. If purity has not been
achieved, repeat the above procedure.
gun
Green raster
Final convergence procedure
(see Fig. 17 through Fig. 19):
Note: Vertical size and focus adjustments must be
completed prior to performing the convergence
adjustment. Connect a dot pattern generator to the
receiver. The BRIGHTNESS level should not be higher
than necessary to obtain a clear pattern.
Converge the red and the blue dots at the center of the
screen by rotating the R&B pole static convergence
magnets.
Align The converged red/blue dots with the green dots
at the center of the screen by rotating the R&B&G pole
static convergence magnets. Melt wax with soldering
iron to reseal the magnets.
Slightly tilt vertically and horizontally (do not rotate) the
deflection yoke to obtain a good overall convergence.
If convergence is not reached at the edges, insert
permalloy (see following section) from the DY corners
to achieve proper convergence. Recheck for purity and
readjust if necessary.
After vertical adjustment of the yoke, insert wedge at 11
o'clock
position,
tilt adjustment.
Secure the deflection yoke by inserting two side
wedges at 3 and 7 o'clock positions.
Apply adhesive between tab (thin portion) of wedge
and CRT and place tape over the tab to secure to
the CRT.
Dynamic corvergence adjustment
Use this for a precisely overall convergence adjust at
the edges.
DY(Y
, Y
, X
) adjustment
HC
V
V
Y
Adjustment
V
(VR1 for Horizontal dynamic convergence)
1. Apply a crosshatch pattern.
2. Adjust contrast and brightness customer controls
to obtain a correct picture.
3. With a driver adjust VR1 (located in deflection yoke
board Fig. 19) to obtain a proper corvergence at
top and bottom of the screen (see Fig. 13)
Figure 13. VR1 Adjustment (Y
- 16 -
then
make
the
horizontal
)
V
B&R
G
B&R
G
B&R
G
B&R
G
Advertisement
Table of Contents
