Factory And Service Adjustments; Amplitude Adjustment; Rgb Amplitude Adjustment; Sub-Contrast Adjustment - Hitachi 32HDT50 Service Manual

Procedure 2
(1) Short PRST connector on the AVC AV PWB and
check that the set return to delivery settings (CH 03).
(2) Do not unplug from AC outlet until this operation is
completed and do not perform any key operation
either. After this operation, each factory setting and
adjust mode data should reset to delivery setting
automatically.

2.2 FACTORY AND SERVICE ADJUSTMENTS

The adjustment item that is affected by the memory
initialize operation is shown below:
Initialization
Adj. Items Memory Init. W/B
Init.(No
need to
use)
Video white affect
blance Adj.
PC white affect
blance Adj.
Video RGB
Amplitude
Adj.
PC RGB
Amplitude
Adj.
Sub-contrast affect
Adj. (M-CONT4;
S-CONT4)
3

AMPLITUDE ADJUSTMENT

(AVC CENTER)

3.1 RGB AMPLITUDE ADJUSTMENT

Preparation
(1) Select "Video" - "Picture Mode" - "Day" - "Reset". Set
"Reset" of "Video" menu when PC input is selected.
(2) Input 525p(480p) of RGB amplitude adj. signal into
INPUT1(Component) input.
(3) Input VGA(60Hz) RGB amplitude adj. signal into
RGB input.
Note: Perform pre heat-run for more than 30 min. before
adjusting.
Adjustment
(1) Receive 525p(480p) signal (Aspect 16:9 Standard).
(2) Select 'RGB(480p)' of Service Adj. menu.
right cursor key ( ) over 2 seconds and have it
perform automatic adjustment. When it's completed,
'Auto Adjusting' on the screen will disappear.
(3) Receive PC signal (VGA(60Hz)), (Aspect Full).
(4) Similarly as (2), select 'RGB(PC)' of Service Adj.
Menu, by pressing SEL button. Press
do automatic adjustment.
-Remarks
RGB amplitude adj. signal
Recommended Equipment:
ASTRO VG-823 Digital Video Generator
with RB-649 Remote Box.
Black White
BACK TO ADJUSTMENTS
Adjustment
change change of change of
of FC- PDP-module I003(EEPR
unit or change of OM) on
I002(EEPROM AV PWB
) on or Memory
SIG/AUDIO Init.
PWB
Adj.
Adj.
Adj.
Adj.
Adj.
Press
for 2 sec. to
0.7V

3.2 SUB-CONTRAST ADJUSTMENT

Preparation
(1) Receive Sub-contrast adjustment signal (Fig. 1).
Adjustment
(1) Select 'SUB CONTRAST' of Service Adj. Menu.
Press for over 2 seconds and have it perform
automatic adjustment. When it's completed, 'Auto
Adjusting' on the screen will be disappeared.
Fig. 1
Full White
V

3.3 BRIGHTNESS CHECK

Preparation
(1) Start checking 20 minutes or more after the power is
turned ON.
(2) Receive the color bar signal.
(3) The vertical incident illumination on the screen
should be 20 lux or less.
(4) Picture Format is 16:9 standard mode.
(5) Select Day mode and reset.
Checking Procedure
(1) Check the brightness as below.
Can be seen at black
Can be seen slightly from black
Note: If set black level is NG, readjust item 3.1 RGB
amp. adj. and 3.2 Sub Contrast adj.
Measuring Conditions
(1) At the signal electric field strength 75± dBu, the
specification mentioned above should be satisfied.
(2) At the input electric field 46-106dBu, there should be
no abnormality.
* From color bar pattern below.
7 step gray scale
A7
A4 has tolerance.
A4 can be between black and
Slightly from black.
31
PT3-E/G AVC3-U
(RF Input ANT A))
V =1.0 Vp-p (when
1
V
1 2
V =100IRE)
2
AVC50
A3*
A5*
10
A6 A5 A4 A3 A2
White 100%
Color Bar Signal
0
A1