White Balance Adjustment; Low-Light White Balance - JVC DT-V1710CG Service Manual

4.10.11 WHITE BALANCE ADJUSTMENTS
LOW-LIGHT WHITE BALANCE (REFERENCE VALUE) ADJUSTMENT
Measuring Instruments
Card (Slot)
Test Points
Adjustment Points
Notes:
•
Perform the following adjustments after completing
the screen size adjustment.
•
Set the COLOR TEMP./BAL. data in the Setup Menu to
"00".
(1) Apply the 1080/60i component crosshatch signals to INPUT
A.
(2) Set "COLOR TEMP." of COLOR TEMP./BAL. in the Setup
Menu to HIGH.
(3) Set the PHASE, CHROMA, BRIGHT and CONTRAST
potentiometers on the front panel to the center click positions.
(4) Observe the AKB pulse waveforms of TP-47R, TP-47G, TP-
47B and ensure that the voltage <A> of the smallest AKB
Pulse color is 25V ± 2V. If it is not, readjust it, using the
SCREEN VR.
(5) Apply the 1080/60i component 10-step gray scale signal to
INPUT A.
(6) Turn the BRIGHT potentiometer on the front panel gradually
until the second gray step in the gray scale lights slightly.
(Do not touch the SCREEN VR potentiometer.)
(7) Adjust WW04, WW05 and WW06 in the Service Menu so
that the gray bars are not tinted. (Do not set the values of
WW04 to WW06 no more than "50".)
(8) Write the data of WW04 to WW06 in WX04 to WX06 without
any alteration. (Do not adjust the WX items.)
Signal generator (Crosshatch signal, 10-step gray scale signal)
Oscilloscope
Component/RGB Input Card (Slot 1)
TP-47R, TP-47G, TP-47B [CRT SOCKET PWB]
TP-GND [CRT SOCKET PWB]
SCREEN VR [Bottom potentiometer on high-voltage transformer]
W*04 (Cut Off (R)), W*05 (Cut Off (G)), W*06 (Cut Off (B)) [Service Menu]
(V. sync)
1 Vertical interval
V. BLK
<A>
25V ± 2V
AKB Pulse
Let this bar light up slightly
(No. 52152) 1-65