JVC DT-V1710CG Service Manual page 56

HORIZONTAL/VERTICAL IMAGE POSITION, IMAGE AMPLITUDE AND IMAGE DISTORTION ADJUSTMENTS (HDTV UNDERSCAN MODE)
Measuring Instruments
Card (Slot)
Test Points
Adjustment Points
Note:
•
Perform the following adjustments after completing
the Reference Mode (HDTV overscan mode)
adjustments.
(1) Apply the 1080/60i size adjustment signal to INPUT A
(Terminal Y on the Component/RGB Input Card).
(2) Set the CONTRAST and BRIGHT potentiometers on the
front panel to the center click positions.
(3) Press the UNDER SCAN button on the front panel to set
the scanning size to underscanning.
(4) Adjust DN04 in the Service Menu to set the vertical position
of the image at the center of the CRT screen.
(5) Adjust DN02 to set the vertical amplitude of the image to
175mm.
(6) Apply the 1080/60i crosshatch signal to INPUT A.
(7) Adjust DN11 to set the sizes of the rectangles at the center
of the image and those at the left and right ends to be
identical.
(8) Adjust DN12 to set the sizes of the rectangles at the center
of the image and those at the top and bottom to be identical.
(9) Ensure that the center position is not deviated. If it is, adjust
DN04 again.
(10) Adjust DN11, DN12 and DN04 repeatedly until the center
position and vertical linearity are optimized.
(11) Adjust DN09 to optimize the trapezoidal distortion (observe
the second vertical lines from the left and right edges as the
reference).
(12) Adjust DN08 to optimize the parallelogram distortion
(observe the second vertical lines from the left and right
edges as the reference).
(13) Adjust DN10 to optimize the horizontal arc distortion.
(14) Adjust DN05 so that the second vertical lines from the left
and right edges are linear.
(15) If there is an extreme corner S-shape distortion, adjust DN07
to optimize it (this adjustment is usually unnecessary).
(16) If there is an extreme corner W-shape distortion, adjust DN06
to optimize it (this adjustment is usually unnecessary).
(17) Apply the 1080/60i size adjustment signal to INPUT A.
(18) Ensure that the vertical amplitude of the image is 175mm. If
it is not, adjust DN02 again.
(19) Adjust DN03 so that the horizontal position of the image
comes at the center of the CRT screen.
(20) Adjust DN01 to set the horizontal amplitude of the image to
311mm.
(21) Vary the adjustment signal and adjustment data, and re-
perform adjustments in steps 1 to 20 above (see Table 9).
1-56 (No. 52152)
Signal generator (Size adjustment signal, Crosshatch signal)
Component/RGB Input Card (Slot 1)
D*01 (Horizontal Size), D*02 (Vertical Size), D*03 (Horizontal Position), D*04 (Vertical Position),
D*05 (Side Pin Distortion), D*06 (Corner Distortion (W)), D*07 (Corner Distortion (S)), D*08
(Parallelogram Distortion), D*09 (Trapezoidal Distortion), D*10 (Horizontal Arc Distortion), D*11
(Vertical Linearity (S Correction)), D*12 (Vertical Linearity (C Correction)) [Service Menu]
Scanning size (100%)
175mm
Screen size
Make these lines linear.
Adjustment Adjustment
Step No. signal
1 1080/60i
2 1080/50i
3 1080/24psF
4 720/60p
5 720/50p
Table 9
311mm
Escutcheon
Adjustment
Data
DN
DR
DT
DV
DX