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ADJUSTMENT INSTRUCTIONS
Y Safety Precautions : PIP VCO Adjustment (For 2TUNER PIP MODEL)
1. It is safe to adjust after using insulating transformer between
the power supply line and chassis input to prevent the risk of Test Point : TP20 on PIP Board
electric shock and protect the instrument.
2. Never disconnect leads while the TV receiver is on. Adjust : LP8
3. Don't short any portion of circuits while power is on.
4. The adjustment must be done by the correct appliances.
1) Turn on the TV set.
5. Unless otherwise noted, set the line voltage to 230Vac!10%,
2) Adjust LP8 so that the waveform of 38.9MHz may be the
50Hz.
same as the figure below.
Y Test Equipment required A : 33.0MHZ
1. RF signal generator (with pattern generator) D
2. DC Power Supply B : 34.5MHZ
3. Multimeter (volt meter) C : 37.25MHZ
4. Oscilloscope A B C E D : 38.9MHZ
5. Color analyzer
E : 41.0MHZ


: Auto Fine Tuning Adjustment

Test Point : TP23 on PIP Board

V Multimeter or Oscilloscope Adjust : LP5

1
J15(ST-BY 5V)
IC101 1) Turn on the TV set.
Power- TDA4474
Supply 2) Adjust LP5 so that the waveform of 38.9MHz may be the
5V R127(IF Vcc) same as the figure below.
0.01pF
C133(+) 24 7 Z103(4PIN) 38.9MHz
11 JP2
R229 D
L104 E:38.9MHz
D:37.25MHz
16 E




Fig. 1 : Connection Diagram of Equipment for PIF Adjustment
: RF AGC (Automatic Gain Control) Adjustment
: PIF (Picture Intermediate Frequency) Adjustment
Test Point : J8 or Observing Display

Adjust : VR101
Test Point : TP1

Adjust : L104 The RF AGC control (VR101) was aligned at the time of
manufacture for optimum performance over a wide range
conditions. Readjustment of VR101 should not be necessary
1) Connect the measuring equipment to the Main Board as
unless unusual local conditions exist, such as ;
shown in Fig.1.
2) Set RF frequency and output level of RF SIGNAL
1) Channel interference in a CATV system.
GENERATOR as shown Table 1.
2) Picture bending and/or color beats, which are unusually due
3) Turn off S1 and S3 and on S2.
to excessive RF signal input when the receiver is too close to
4) Adjust L104 so that the DC voltage may be 2.5!0.1Vdc.
a transmitting tower or when the receiver is connected to an
antenna distribution system where the RF signal has been
System Frequency Modulation Output level Adjust amplified. In this case, the input signal should be attenuated
B/G,D/K/I,M 38.9MHz OFF 10mVp-p L104 (with pad or filter) to a satisfactory level.
3) Picture noise caused by "broadcast noise" or weak signal.
(Table 1) If the broadcast is "clean" and the RF signal is at least 1mV
(60dBu), the picture will be noise free in any area.


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Adjusting the VR101(RF AGC) control to one end of rotation
will usually cause a relatively poor signal to noise ratio;
Adjusting to the other end of rotation will usually cause a
degradation of over load capabilities resulting in color beats or A B
adjacent channel interference. For best results, adjust the
VR101 control while performing on all over local channels, or
the voltage at TP2 will be 2.3!0.1Vdc in RF level 65!1dBuV.




: Screen Voltage Adjustment

Fig. 3 b
Test Point : CPT Face

Adjust : Screen Control of FBT : Deflection Data Adjustment (Line SVC-1)

1. Preparation for Deflection Adjustment
NOTE: To enter SVC mode, press "OK" buttons on both TV 1) At SVC mode, press the Yellow colored button.
set and the Remote control at the same time. If the Remote Controller doesn't have the Yellow button,
use the button under the Channel Down(PR E) button.
1) Tune the TV set to receive a digital pattern. And then, deflection data adjustment OSD (SVC1 mode)
2) Press MIX button on remote controller for Service to get will be displayed.
into the Screen Adjust Mode. 2) Press Channel UP/DOWN button for desirous function
3) Adhere the Color Analyzer on the White window of CPT Adjustment.
face. 3) Press Volume UP/DOWN button to adjust the data.
4) Adjust Screen Volume of FBT so that the luminance of
White window is 42!1 FL.
VL (Vertical Linearity)
Adjust so that the boundary line between upper and lower
White window OSD half is in accord with geometric horizontal center of the CPT.

VA (Vertical Amplitude)
Adjust so that the circle of a digital circle pattern may be
located within the effective screen of the CPT.

SC (Vertical "S" Correction)
SCREEN ADJUST MODE
Adjust so that all distance between each horizontal lines
are to be the same.
Fig. 2 SVC MODE for SCREEN Adjust
VS (Vertical Shift)
Adjust so that the horizontal center line of a digital circle
pattern is in accord with geometric horizontal center of
: Focus Adjustment the CPT.

NOTE: This adjustment should be performed after warming HS (Horizontal Shift)
up for 10 minutes. Adjust so that the vertical center line of a digital circle pattern
is in accord with geometric vertical center of the CPT.
Test Point : Observing Display
EW (Horizontal Width)
Adjust : Focus control of FBT Adjust to that a digital circle pattern looks like exact circle.

EP (East-west Parabolar)
1) Tune the TV set to receive a digital pattern. Adjust so that middle portion of the outermost left and right
2) Adjust the lower Focus control of FBT for the best focus of vertical line looks like parallel with vertical lines of the CPT.
vertical line B.
3) Adjust the upper Focus control of FBT for the best focus of EC (East-west Coner)
area A. Adjust so that the vertical line at every 4 corners of the
4) Repeat above step 2) and 3) for the best overall focus. screen looks like parallel with the vertical lines of the CPT.

ET (East-west Trapezium)
Adjust to make the length of top horizontal line same with
it of the bottom horizontal line.


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