High Voltage Phase Adjustment - Hitachi 36SDX88B Service Manual

2.3.3 High Voltage Phase Adjustment Adj. point RHO7
Preparation for adjustment
Adjustment procedure
Notes
(1) Receive Cross-Hatch and +I) Adjust wave form as shown below with
Circle Pattern with white
background of VGA3 in
turning High-Voltage Phase Adjustment
group 1
VR RH07.
(2) Set Brightness control to
the center, and Contrast
control to the maximum.
(3) Connect probe to Collector
of Q705 and QH02.
~~ ;&$yE;;;bes should be
: :
I I Voltage wave form of
I
: I
: :
QH02 Collector.
: :
: :
: : Confirm that the wave form
: :
4kL
: :
meet adjustment spec. wher
I I
I 1
receiving SVGA of group 1.
Voltage wave form of
Q705 Collector.
1 .o !r 0.5 p s
2.3.4 High Voltage Limiter Operation Check
Adj. point R763
('I ) Set AC Voltage to 120 f 2V.
1) Connect Jig B between both ends of
RH38 and check that power turns
off and standby mode is set.
c
B RH38
(2) Receive Cross-Hatch Signal (2) Disconnect AC plug.
L
DH22
with Black Lines and 100%
RI-l39
White background of VGA3.
(3) Set Brightness and
(3) Remove Jig B and turn the main
Contrast to the maximum.
power on. Check if power is supplied
Jig B ; b= 4.7k R (1/4W)
and High Voltage rises. RB
4- J# b
49