Seanix 42PSEA06, Service Manual

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ATSC+NTSC TV RF signal are separated into 2 way output when enter into Tuner. One is NTSC
(Analog signal) that output video signal by mixing, amplifying, demodulating. Video signal are
separated into Y/C signal throughTEA6415C, and transferred into ITU601 through ADV7401, then
send into Video-audio process chip Generation9. Tuner output SIF audio signal to MSP3450G to
process, amplify, then put in D-type amplifier TA2024.
The other ATSC (Digital signal, ATSC channel bandwidth is 6MHZ) via Tuner transferred into
TS-stream through 44MHZ intermediate frequency amplify, ASW filter, QAM\OFDM demodulate,
then enter into Generation-9 to MPEG decode, video part revert into video signal through coding,
and transferred into double-field TTL signal by this chip process. Then put into Scaler and LVDS
drive chip DS90C2501, through coding output 5 pair LVDS signal to drive PDP panel module.
Digital audio signal from Generation-9 revert into Audio signal to MSP3450G through PCM
decoding.
Program information in TS-stream be parsed and stored, user could know related program
information through OSD query menu. For multi-program TS-stream, user could appoint to see
some program in this stream through program guide EPG.
AV, S-video, YPBPR, DVI, D-Sub and each Audio signal through two group of 74HC4052
switch with ATSC audio signal together put into MSP3450G, through alt, woof, balance, volume,
SRS, BEE process, then amplify by D power amplifier TA2024,output to loud-speaker.
9-2-2 Input signal introduce
1. VIDEO: transmit bright & chroma signal , it is general ,its picture quality is equal to the general VCD.
S-VIDEO transmit the bright and the chroma single, and can reduce/control the cross-interfere , it is better
than the Video.
2. RGB&D-SUB (Pc interface ): general RGB simulative input interface .
3. YCbCr(NTSC/PAL): is composed of one bright and two chromatism signals U/V. due to the eye is more
sensitive for bright than chroma , RGB via the formulae Y=0.39R+0.50G+0.11B to transform into one bright
and two chromatism signals U(R-Y), V(B-Y).
4. VIDEO
、
S-VIDEO
、
YCBCR : the frequency 15.6KHZ 50(PAL)/60HZ(NTSC), interleaved simulative signal.
5. YPbPr: non-interlaced signal, belong to DTV scope, support 480P,720P,1080i format, current is NTSC.
6. DVI ： digital Visual Interface, has 29pin （ DVI-I ） and 25pin (DVI-D), now many top grade display card own it.