LG 21FS2CG, Service Manual

Page: 9 / 33

1. Scope of Application
These instructions are applied to MC-059C Chassis.
2. Notes
1) Because this is a cold chassis, it is not necessary to use an
isolation transformer. However, operating it using a
transformer between the power supply line and chassis input
to prevent electric shock and to protect the test instrument.
2) All adjustment must be done in the correct sequence.
However, for better productivity, it can be change in a pre-
permitted range.
3) Environment conditions : If not specified, it must be done in
following conditions.
Temperature : 25 ± 5°C
Humidity
60% ± 10%
4) Power supply of SET : AC100-240~ ± 10%, 50/60Hz
5) If not specified, the receiver must be operated for more than
20 minutes prior to the adjustment.
6) Signal : Received the standard color signal (65±1dBuV).
- NTSC
: LG standard signal means the digital pattern 13CH(480NC)
- PAL/SECAM
: LG standard signal means the digital pattern PAL-B/G 05CH
7) If not specified, APC ON is APC CLEAR(DYNAMIC)
3. AGC Voltage Adjustment
3-1. Necessary Instrument
: Digital Multi-meter-1 set
- Max Input Current : Over 1A/ Max Input Voltage : 500Vdc
- Measurement Range : 10mV-100mVdc/ Accuracy : 0.03%
3-2. Adjustment Preparation
1) Input in the 75
Ω
cable 65dB(±1dB) LG standard signal.
2) Connect the multi-meter to J105(AGC Check, Marking).
3-3. Adjustment
1) Press the “INSTART” key of factory remote control and
select “VP0 (RFAGC)” adjustment mode.
2) Press the VOL+/-(
F
/
G
) key until the multi-meter shows
reading as shown below.
3) CAUTION
: Since the signal strength can be easily changed by the
condition of signal cable, you need to check the signal
strength frequently in order to prevent error.
4. Screen Voltage Adjustment
4-1. Adjustment of Screen Manually
(Using SVC Remote Control)
1) Input in the 75ohm cable LG standard signal(Digital Pattern,
480NC).
2) Press the “ADJ’ key of factory remote control once to make
the TV set display.
3) Turn the screen volume on the FBT clockwise until the
horizontal line is visible and turn it counterclockwise until
horizontal line faintly visible.
(Exit screen voltage adjustment by press “Enter(
A
)” key of
factory remote control.)
5. Purity and Convergence Adjustment
5-1. Purity adjustment
(1) Adjustment Preparation
1) Receive Red Raster Pattern for purity adjustment(51CH).
2) Demagnetize the CPT and Cabinet with a degaussing coil.
(2) Adjustment
1) Pre-adjust the static convergence (STC) with the 4 and
6pole magnet.
2) If the horizontal Line is inline with CPT Mark, 2-Pole
magnet should direct 3-9 o’clock direction.
3) If not, direct 2-pole magnet handle toward 6-12 o’clock
direction and adjust the Horizontal Line to fall onto the
mark opening the magnet at an angle.
4) Push the DY(deflection yoke) all the way to the CPT
funnel.
5) Turn the purity magnet(2-pole magnet) so that the “green”
color portion of left side and the “blue” color portion on the
right side have equal amount of color.
6) Pull the DY slowly backward and fix it when the whole
screen becomes red.
(The specified torque for fixing DY screw should be
10Kg/cm.)
5-2. Convergency Adjustment
(1) Necessary Instrument
1) Degaussing Coil
2) Convergency fixing instrument
(2) Preliminary steps
1) Operate the unit at the least 30minutes before adjustment.
2) Using degaussing coil, remove the stains on CPT &
Cabinet.
3) Received the Cross Hatch Pattern of Convergence.(09ch)
4) Let the Contrast in normal luminance level
.
G R B
- 9 -
ADJUSTMENT
G R B
R G R B
6700VS0002F
6700PF0002F
6700MF0014A
6700MF0014B
LGIT
SANYO
LGIT
LGIT
3.0 ± 0.05V
2.3 ± 0.05V
2.3 ± 0.05V
2.15 ± 0.05V
70dBu
65dBu
65dBu
65dBu
TAEW-G002D
115-B-A86EL
TAEW-G013D
TAEW-G017D CIS
Tuner P/N Maker AGC Vol Signal Tuner Spec. Remark