Panasonic gp8du gph8du th-37px50u th-42pd50u th-42px50u th-42px500u th-50px50u th-50px500u troubleshooting Service Manual

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Analog Television signals are output to the H board and selected like any other source. 
Digital television signals (Y, Pb, Pr) are output to the DG board for video selection and 
processing. 
 
The K board contains the optical sensor used for CATS (Contrast Automatic tracking 
System). It also contains the Remote IR sensor and the power LED. 
 
The unit contains two video inputs, two component inputs, and a PC input (depending 
upon the model) that are directly connected to the main switch of the H board. 
 
The H board selects and outputs, to the DG board, the main video and sub video 
signals for display on the screen. 
 
The DG board is responsible for the complete video processing within the unit. All 
analog inputs to the DG board are immediately converted to digital. All signal 
processing in the DG board
 
is performed digitally. Signals from a digital TV or HDMI 
source are provided to the DG board in digital form. The board performs PIP (Picture in 
Picture) and
 
picture control operations such as brightness, contrast, color, tint, etc. The 
board also performs pixel conversion to change the resolution of the picture to the 
resolution of the screen. The output signal of the board passes through an LVDS (Low 
Voltage Differential Signaling) transmitter for conversion into serial data. The PEAKS 
firmware of the unit also resides in this board. 
 
The D board is responsible for displaying the picture on the screen. It provides the scan, 
sustain and data drive signals. The scan pulses are output to the SC board. The sustain 
pulses are output to the SS board. The data drive signals are output to the C1, C2, C3 
and C4 boards. The C1 board drives the upper right portion of the panel; the C2 board 
drives the upper left portion. The C3 and C4 boards drive the lower right and left 
portions of the panel respectively. 
 
The SC board is responsible for the generation of the scan pulses. Scan pulses are 
used for initialization and selection of the pixels. 
 
The SU and SD boards are demultiplexer boards that are responsible for converting 
serial data output of the SC board into parallel data to drive the panel. 
 
The SS board is responsible for the generation of the sustain pulses. Sustain pulses are 
used to initialize and control the brightness of the screen. 
 
 
 
 
 
 
 
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