XOCECO LC-26U26, Руководство по обслуживанию

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Working principle analysis of the unit
The RF signal received by antenna will be sent to tuner, then IF signal will be obtained through high
amplifier and mixed frequency, through pre-intermediate amplified by V104, then it will be sent to
acoustic surface-wave Z103 to do IF filter and get better IF characteristics, then it will be sent to TV
board N101 (M52760E) to do intermediate amplification, phase-locked loop VCO and synchronous
wave detection to get composite video signal VIDEO; after pre-intermediate amplification IF will also
be sent to acoustic surface-wave Z102 to do filter at the same time, then it will be sent to N101 to do
intermediate amplification and demodulate audio signal (SIF).
The VIDEO signal output from M52760E together with video signals namely AV1 and AV2/S will be
sent to video decoder N601 (TVP5160) to de video selection, clamp, A/D transformation,
comb-shaped filter and color decode, then one way will output as video output of AV OUT, one way
will output 8bit CCIR656 format signal and CLK signal, then it will be sent to the main chip N101
(MST6151) of CPU; YpbPr, VGA and HDMI signals will also be sent to N101 (DVI interface can be
connected to HDMI interface through the use of a passive cable converter).The main chip
N101(MST6151) a multifunctional large-scale specified integrated circuit board, it has many kinds of
function such as A/D and D/A transformation, interleaved/ line-by-line processing, mode
transformation, low voltage differential output processing etc., then output four couples differential
signal and one couple clock signal.
The signals input from HDMI to MST6151 include audio signal, after processing in MST6151, it will
be sent to NA01 (CS4340) to do D/A transformation and then output audio signal L/R of HDMI.
Audio signal L/R of HDMI output from CS4340 output together with audio signal L/R of YPbPr and
VGA/DVI will be sent to audio processor N801 (MSP3425G) after selection by audio switch NA02
(HEF4052); L/R signal of AV1 and AV2/S via selected switch N701(HEF4052) will also be sent to
N801,and SIF of TV output from M52760E send to N801 too. In MSP3425G, the demodulated L/R
of SIF and the input L/R from other two ways, via selected switch and processing sound, then
output signal, one way sound output for AV OUT, other way send to N401(TPA3008D2) of sound
amplifier, via amplify for sound signal to speaker.
The whole unit is controlled by CPU (N801) MM502, it can be connected to tuner, TVP5160 and
MSP3425G etc. through IIC bus; and connected to MST6151 through parallel BUS and control
them.