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- 17 -

No Raster on AV Signa
(Video1,Video2, S-Video)

No Raster on TV(RF) signal

Change C316,C317,
Q308,Q313

Check the signal of 

C316,C317,Q308,Q313

Repeat

[A] Process 

Check the output of 

TU1000

Check the input/output 

of IC1 

Check the input/output 

of IC500, IC600

Check input source cable and  jack 

Faill

Faill

Faill

Faill

Re-soldering or
Change the defect part

Faill

Re-soldering or
Change the defect part

Check 5V, 33V of TU1000
Re-soldering or 
Change the defect part

Pass

Pass

Pass

Check the input/output 

of IC901

Faill

Re-soldering or 
Change the defect part

Pass

Pass

- 18 -

No Sound

Check the speaker wire

Change source input

Check the 

input source

Faill

Pass

Re-soldering or 
Change the defect part

Check the input/output 

of IC1

Faill

Pass

Re-soldering or 
Change the defect part

Check the input/output 

of IC100,IC101 

Faill

Pass

Change speaker

Check the speaker

Faill

Pass

- 19 -

- 20 -

Video signal is received from  TUNER, AV port(AV1,AV2,S-Video) and goes to the one-chip video decoder
(VCTI) which separate the R,G,B signal and passes on the signal to AD converter(AD9883) through the video
switch(SM5301). Component signal(YPbPr) from side-jack is also passed to video switch(SM5301) and Micom
will select the desired signal(RGB from VCTi or Component from side jack).
The AD9883 converts 4:4:4 video format into digital and gives output to the Picture Enhancer (FLI2300).This
picture enhancer improves the quality of the picture by changing the level of RGB/YPbPr signals.The output of
this enhancer chip is fed to the deinterlacer ,which in turn  goes to the Scalar (GM5221).The  scalar  gives the
output on the LVDS cable which is connected to LCD module.
VCTi acts a micom and is responsible for video processing and audio signal processing.It accepts the RF
precessed signal(IF signal) from tuner/SAW-Filter and separates sound and picture from it.
Scaler is reponsible for regulating the timing of signal to LCD panel and size and location of the signal. Graphic
control accepts the PC(Analog RGB) and DVI-D (Digital) signal. The signal of PC input is connected to analog
port in Scaler and the signal of DVI-D input is connected to digital port. Thus it receives two input and switch
between them to give output at the LVDS which in turn gives output at the LCD module. 

The power board supplies a DC voltage of 33V(main power), 24V(Stand_by power), 12V(Stand_by power) to
the main board. Main power is only available after power-on and Stand_by is always available. 33V is used by
the tuner and 24V is used directly by the inverter and the sound amplifier IC. 24V also is converted into 5V-Main
Power and 5V-Stand_by by a DC/DC Converter(MP1593). The 5V is changed into 3.3V and 1.8V by a regulator.
Both voltages(3.3V, 1.8V ) is used by VCTI, Scaler, FLI2300 and AD9883. The voltage of LCD Panel is 12V