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Explanation for circuit operation
4. Video signal process
4-1. Block Diagram
4-2. Video processor
This part switches and processes DTV input, DVD input, external video signal and TV
signal.
1) Signal input/output
The signal input is composed of 2 pairs of NTSC TV signals (2 tuners), 3 pairs of NTSC
external inputs (Video, S-VHS 3 pairs respectively), 2 pairs of component inputs and 1 pair
of monitor outputs.
2) Video input switching
2 pairs of NTSC TV signals and 3 pairs of NTSC external input from the main tuner
(TU701) and sub tuner (TU702) is switching in a IA01 AV switch and 2 pairs of component
input is switching in a IA05 video selector.
CXA1855Q outputs 4 pairs as switching IC with 5 pairs input and CXA2151Q outputs a
YCbCr signal by 4 pairs input. The output signal is amplified 6dB.
CVBS (Main) and Y, C signal from QXA1855Q are input to 3D Comb-filter (ICB1), 4801
format between CVBS (Sub) and IA05 output is input to ICD1 and 480P and 10801 signal
of IA05 are input to IC201.
ICB1 performs Y, C division and YCNR (YC Noise Reduction) function, equipped with
internal AD converter and 4M bit frame delay memory as a three-dimensional Y, C divided
IC.
Y/C signal from ICB1, caption data decoded in caption IC (IC206) and 4801 signal of IA05
are input to the main video processor IC, VSP9407B (ICD1).
