High-Definition Signal Flow; Sound Signal Flow; Volume Control; Mute Control - TCL SY33 Service Manual

Video signal of AV2 from pin4of P901 is sent to pin54 of IC201 to decode process.
Sound signals of AV2 from pin5 and pin6 of P901 is sent to pin1 and pin 12 to choose
signal,.After being choosed, the signal flow same as TV sound.

3) High-Definition signal flow.

Y signal from pin7 of P901 enters pin48 of IC201 to process video.
Cb signa from pin8 of P901 enters pin49 of IC201 to process video.
Cr signal from pin9 of P901 enters pin51 of IC201 to process video.

4) Sound signal flow

Volume control:

Sound signal from pin27 and pin28 of IC201 enters pin6 and pin13 of IC601 to be amplified
and be sent out form pin8 and pin12 of IC601.

Mute control:

Pin30 of IC201 sends mute control signal, and passes D002 to connect base of Q602,controls
the Q602 ON or OFF, the pin C of Q602 connects pin5 of IC601 to control mute normal
working .When Q602 off, pin5 of IC601 is high level. So pin8 and pin12 of sound signal output
to speaker, when MCU sent mute signal of high level,Q602 ON, it lets the pin5 of IC601 is low
level to shut down the sound signal of pin8/pin12 of IC601, the mute is working.
TU101 is a common tuner. The RF signal is processed by tuner inside circuit disposal :high
frequency amplifier 、 mixing、 high frequency demodulation、 AGC、 AFT、 PLL。 Then IF output
signal from pinIF of TU101 passes preamplifier Q101 to enter SAW Z101. The PIF signal from
pin4 and pin5 of Z101, enters pin63 and pin64 of IC201 to be decoded.