Daewoo WP-895F, CP-885F service manual

Page 45

Service manual WP 895/895F, CP885/885F

5-2-5 Video Demodulation and Amplifier

The video IF signal, which is applied from the gain controlled IF amplifier, is multiplied with the in-phase component of the VCO signal. The video demodulator is designed for low distortion and large bandwidth. The demodulator output signal passes an integrated low pass filter for attenuation of the residual vision carrier and is fed to the video amplifier. The video amplifier is realised by an operational amplifier with internal feedback and 8 MHz bandwidth (–3 dB). A standard dependent dc level shift in this stage delivers the same sync. level for positive and negative modulation. An additional noise clipping is provided. The video signal is fed to VIF-AGC and to the video output buffer. This amplifier with a 6 dB gain offers easy adaptation of the sound trap. For nominal video IF modulation the video output signal at Pin 12 is 2 Vpp.

5-2-6 Sound IF Amplifier and SIF-AGC

The SIF amplifier is nearly identical with the 3-stage VIF amplifier. Only the first amplifier stage exists twice and is switchable by a control voltage at Pin 3. Therefore with minimal external expense it is possible to switch between two different SAW filters. Both SIF inputs features excellent cross-talk attenuation and an input impedance which is independent from the switching condition. The SIF-AGC is related to the average level of AM- or FM-carrier and controls the SIF amplifier to provide a constant SIF signal to the AM demodulator and QPS mixer.

5-2-7 Quasi-Parallel-Sound (QPS) Mixer

The QPS mixer is realised by a multiplier. The SIF signal (FM or NICAM carrier) is converted to the intercarrier frequency by the regenerated picture carrier (quadrature signal) which is provided from the VCO. The intercarrier signal is fed via an output amplifier to Pin 24.

5-2-8 Standard Switch

To have equal polarity of the video output signal the polarity can be switched in the demodulation stage in accordance with the TV standard. Additionally a standard dependent dc level shift in the video amplifier delivers the same sync. level. In parallel to this, the correct VIF-AGC is selected for positive or negative modulated VIF signals. In the case of negative modulation (e.g., B/G standard) the AM output signal is switched off. For positive modulation (L standard) the AM demodulator and QPS mixer is active. This condition allows a parallel operation of the AM sound signal and the NICAM-L stereo sound.

5-2-9 L’ Switch

With a control voltage at Pin 14 the VCO frequency can be switched for setting to the required L’ value (L’ standard). Also a fine adjustment of the L’-VCO center frequency is possible via a potentiometer. The L’ switch is only active for positive modulated video IF-signals (standard switch in L mode).

5-2-10 Internal Voltage Stabiliser

The internal bandgap reference ensures constant performance independent of supply voltage and temperature.

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Contents Colour Television Contents Circuit description PCB Layout Circuit Diagram Power consumption Main FeaturesSound Output Power Tuning systemSpecification matrix Pin Signal Description Matching value Page C02 C01C03 C04C42 S11 S10S12 S13Special case Country selection = Others Program Group SkipITV RAY Radiation Precaution Safety instructionAlignment instructions Order Default settingh for wpParabola HOR WidthDisable HOR Paral BOW Corner EW Trapez IC description Page Page IC version VCT 3832A Chassis IC marking OSD languages Atss countries TextPin Name Type Short Description Gndaf Supply VCT Page Analogue Section DSP-Section Audio Baseband ProcessingNicam plus FM/AM-Mono German 2-Carrier System Dual FM SystemSECAM-L PALUssr AdrselDvsup ANAIN1 FeaturesTesten XtalinPin Symbol Function GND1 OUT1OUT1+ ModeBlock diagram TDA8944J GND Page Page Inverting input Block diagram TDA6107Q SCL SDAPage Description IC PIN Symbol Rating Unit OCH -F MINCircuit description If section Block diagram Vision if Amplifier Standard Features Page Page Adaptive Comb Filter VCT3834A only Video Sync Processing CRT Measurement and Control Page Stand by ConfigurationDescription Application Page Page Quadrature Mixers ESCPage Page STR-F6654 general description Power supply primary part operationsPage STR-F6654 oscillating operation Latch circuit Overcurrent protection function OCPThermal shutdown circuit TSD Overvoltage protection circuit OVPTV start-up operations TV normal run and stand-by mode operations Page FBT CP885/885F N T R O L L E D Rectifier 6V DC High Service Parts List Spark GAP CBXF1H104Z Cera Semi 50V F 0.1MF Z Tapping CZSL1H220J Cera 50V SL 22PF J Axial CCZB1H222K Cera Coil Peaking Wire Copper Carbon Comp Exploded View Exploded View DTF-29U8 DTP-28A7 Service Man ual WP-895/895F, CP885/885F DTP-28G7 DTP-28G8 Printed Circuit Board Page Page 686, AHYEON-DONG MAPO-GU SEOUL, Korea

CP-885F, CP-885, WP-895, WP-895F specifications

The Daewoo WP-895F, WP-895, CP-885, and CP-885F are versatile washing machines that embody the brand’s commitment to quality and innovation. These models are designed to meet the diverse needs of modern households, offering a range of features that enhance laundry efficiency and user convenience.

The WP-895F and WP-895 are known for their user-friendly design and robust functionality. They come equipped with advanced washing programs that cater to various fabric types, ensuring optimum care for garments. One of the standout features of these models is the 10kg capacity, which is ideal for larger families or those who frequently do laundry. The machines boast an energy-efficient motor that reduces power consumption while delivering superior washing performance.

Integrated with smart sensors, the WP-895F and WP-895 adjust water levels according to the load size, optimizing resource usage and making washing more economical. Additionally, the models feature a delayed start option, allowing users to schedule wash cycles at their convenience.

On the other hand, the CP-885 and CP-885F stand out for their compact design and functionality. Ideal for apartments or smaller spaces, these machines offer a 7.5kg capacity while delivering impressive wash quality. They include specialized washing modes for delicates, heavy-duty fabrics, and quick washes, thus accommodating a wide range of laundry needs.

Both CP models are designed with user comfort in mind, featuring intuitive control panels that simplify operation. The CP-885F includes an enhanced filtration system that captures lint and other particles, ensuring cleaner wash results while prolonging the machine's lifespan.

Each model incorporates durable and reliable technology, with stainless steel drums that resist rust and enhance longevity. The noise reduction technology also ensures that laundry day remains a peaceful experience, reducing operational sound levels significantly.

Overall, the Daewoo WP-895F, WP-895, CP-885, and CP-885F are equipped with essential features and cutting-edge technologies that cater to the evolving demands of households. With their combination of efficiency, capacity, and innovative design, these washing machines exemplify Daewoo's dedication to improving everyday laundry experiences. Whether for large families or smaller living spaces, these models provide robust solutions that make laundry tasks simpler and more effective.