(No.YA193)1-17
4.7
ADJUSTMENT PROCEDURE
4.7.1 B1 VOLTAGE
4.7.2 FOCUS ADJUSTMENT
4.7.3 IF CIRCUIT ADJUSTMENTS
Item
Measuring
instrument
Test point
Adjustment part
Description
B1 VOLTAGE
check
Signal
generator
DC voltmeter
B1 (pin 1)
GND (pin 5)
[CN00X
connector in
MAIN PWB]
(1) Receive a black and white signal.
(2) Connect a DC voltmeter between B1 and GND
(between pins 1 and 5 of the connector CN00X).
(3) Make sure that the voltage is
DC134.5V
±
2V
.
Item
Measuring
instrument
Test point
Adjustment part
Description
FOCUS
adjustment
Signal
generator
FOCUS VR
[In HVT]
Notes:
• Set PICTURE MODE (VSM) to "BRIGHT".
• The final adjustment of CONVERGENCE must be
done after the FOCUS adjustment. (CONVERGENCE
is affected by the FOCUS adjustment.)
If any aeviation in CONVERGENCE is found, PURITY
must be adjusted to restore the convergence.
(1) Receive a crosshatch signal.
(2) Adjust the
FOCUS VR
so that the vertical and
horizontal lines will be clear and in fine detail on the
screen.
(3) Make sure that the picture is in focus even when the
screen gets darkened.
Item
Measuring
instrument
Test point
Adjustment part
Description
IF VCO
check
Remote
control unit
[1. IF]
1. VCO (CW)
Note:
• Under normal conditions, no adjustment is required.
(1) Receive a broadcast signal.
(2) Select
1. IF
from the SERVICE MENU.
(3) Select
1. VCO
.
(4) Check the characters colour of the
JUST
REFERENCE
displayed to
yellow
.
(5) Press the [DISPLAY] key three times to return to
normal screen.
DELAY POINT
(AGC
TAKE-OVER)
adjustment
Remote
control unit
[1. IF]
2. DELAY POINT
(1) Receive a black and white broadcast signal (colour off).
(2) Select
1. IF
from the SERVICE MENU.
(3) Select
2. DELAY POINT
.
(4) Adjust in order to eliminate any noise or beat from
the image. Any increase above the initial value
produces the noise and any decrease below it
produces the beat.
(5) Press the [DISPLAY] key three times to return to the
normal screen.
(6) Turn to other channels and make sure that there are
no irregularities.
TOO HIGH
ABOVE REFERENCE
BELOW REFERENCE
JUST REFERENCE
TOO LOW
VCO (CW)
.
MHz
DISPLAY : EXIT
Receiving frequency
YELLOW
Initial setting value
Adjustment item
NTSC 3.58 OTHERS
VHF UHF VHF UHF
2. DELAY POINT
(AGC TAKE-OVER)
35
35
35
35