Adjustment - LG 21FG1AL Service Manual

1. Scope of Application
These instructions are applied to CW81A 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: 65% ± 10%
4) Power supply of SET for PAL/SECAM
China/indonesia/Vietnam/CIS Market: AC100~240V±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 (65dB±1dBuV).
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 75Ω 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 (RF AGC)" adjustment mode.
2) Press the VOL+/- (
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.
Tuner P/N Maker AGC Vol
6700NFNS11E LGIT 2.15 ± 0.05V
6700VS0002F LGIT 3.0 ± 0.05V
6700PF0006B SANYO 2.3 ± 0.05V
6870NB0026A LGIT 2.15 ± 0.05V
6700MF0014A LGIT 2.3 ± 0.05V
6700MF0018A
LGIT 2.5 ± 0.05V
6700MF0018B LGIT 2.4 ± 0.05V
6700MF0018D LGIT 2.4 ± 0.05V
6700MF0018E LGIT 2.5 ± 0.05V
Copyright©2008 LG Electronics.Inc. All right reserved.
Only for training and service purposes.
ADJUSTMENT
F G
/ ) key until the multi-meter shows
Signal Tuner Spec.
65dBu TAEA-H111F
65dBu TAEW-G002D
65dBu 115-B-A86EL
65dBu TAEA-J001F
65dBu TAEW-G013D
SECAM(CIS)
65dBu TAEA-G011D
65dBu TAEA-G001D
65dBu TAEA-G011D
65dBu TAEA-G111D SECAM(CIS)
4. Screen Voltage Adjustment
4-1. Adjustment
1) Input in the 75Ω cable LG standard signal (Digital Pattern,
480NC).
2) Press the "ADJ' key of factory remote control once to make
the TV set display horizontal line.
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(
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
Remark
1) Degaussing Coil
Korea
2) Convergency fixing instrument (Speical tools)
PAL
PAL
(2) Adjustment Preparation
HITACHI
PAL 1) Operate the unit at least 15 minutes before adjustment.
2) Using degaussing coil, remove the stains on CPT &
PAL
Cabinet.
PAL
3) Received the Cross Hatch Pattern of Convergence. (09ch)
4) Let the Contrast in normal luminance level .
(3) Static Convergence (STC) Adjustment
1) Receive the Cross Hatch Pattern Convergence (09ch).
- 6 -
(Using Factory Remote Control)
G
G R B
G R B
A )" key of
R B
R
LGE Internal Use Only