Daewoo DTX-21B4, Service Manual

CP-520

V

 Service Manual 

21

windows in parallel. 
·   Linear and non-linear horizontal scaling of the video signal to be displayed. 

Sound Demodulation (all versions) 

·   Separate SIF (Sound IF) input for single reference QSS (Quasi Split Sound) demodulation. 
·   AM demodulator without extra reference circuit 
·   The mono intercarrier sound circuit has a selective FM-PLL demodulator which can be switched 
to the different FM sound frequencies (4.5/5.5/6.0/6.5 MHz). The quality of this system is such 
that the external band-pass filters can be omitted. In the stereo versions of UOCIII the use of this 
demodulator is optional for special applications. Normally the FM demodulators of the stereo 
demodulator/decoder part are used (see below). 
·   The FM-PLL demodulator can be set to centre frequencies of 4.72/5.74 MHz so that a second 
sound channel can be demodulated. In such an application it is necessary that an external 
bandpass filter is inserted. 
·   The vision IF and mono intercarrier sound circuit can be used for the demodulation of FM radio 
signals. With an external FM tuner also signals with an IF frequency of 10.7 MHz can be 
demodulated. 
·   Switch to select between 2nd SIF from QSS demodulation or external FM (SSIF) 

Audio Interfaces and switching (stereo versions with Audio DSP) 

·   Audio switch circuit with 4 stereo inputs, a stereo output for SCART/CINCH, 1 stereo output for 
HEADPHONE. The headphone channel has an analogue volume control circuit for the L and R 
channel. Finally 1 stereo SPEAKER output with digital controls. 
·   AVL (Automatic Volume Levelling) circuit for the headphone channel. 
·   Digital input crossbar switch for all digital signal sources and destinations 
·   Digital output crossbar for exchange of channel processing functionality 
·   Digital audio input interface (stereo I2S input interface) 
·   Digital audio output interface (stereo I2S output interface) 

Audio interfaces and switching (AV stereo versions without Audio DSP) 

·   Audio switch circuit with 4 stereo inputs, a stereo output for SCART/CINCH and a stereo 
SPEAKER output with analogue volume control. 
·   Analogue mono AVL circuit at left audio channel 

Audio interfaces and switching (mono versions) 

·   Audio switch circuit with 4 external audio (mono) inputs and a volume controlled output 
·   AVL circuit 

Stereo Demodulator and Decoder (full stereo versions) 

·   Demodulator and Decoder Easy Programming (DDEP) 
·   Auto standard detection (ASD) 
·   Static Standard Selection (SSS) 
·   DQPSK demodulation for different standards, simultaneously with 1-channel FM demodulation 
·   NICAM decoding (B/G, I, D/K and L standard) 
·   Two-carrier multistandard FM demodulation (B/G, D/K and M standard) 
·   Decoding for three analog multi-channel systems (A2, A2+ and A2*) and satellite sound 
·   Adaptive de-emphasis for satellite FM 
·   Optional AM demodulation for system L, simultaneously with NICAM 
·   Identification A2 systems (B/G, D/K and M standard) with different identification time constants 
·   FM pilot carrier present detector 
·   Monitor selection for FM/AM DC values and signals, with peak and quasi peak detection option 
·   BTSC MPX decoder 
·   SAP decoder 
·   dbx® noise reduction (4) 
·   Japan (EIAJ) decoder 
·   FM radio decoder 
·   Soft-mute for DEMDEC outputs DEC, MONO and SAP