Friday, 5 February 2021

Pioneer PDI-P23LCD TV-PAL, SECAM-NTSC – 23 inch LCD TV-How to enter the service mode, adjustments, schematic

 

  Always respect voltages. While some may not be dangerous in themselves, they can cause unexpected reactions that are best avoided. Before reaching into a powered TV set, it is best to test the high voltage insulation. It is easy to do, and is a good service precaution.

It makes sense to avoid exposure to electrical shock.  While some sources are expected to have a possible dangerous impact, others of quite high potential are of limited current and are sometimes held in less regard.

External in/output
PC ANALOG INPUT, PC DIGITAL INPUT, PC AUDIO INPUT, HEADPHONE OUTPUT, COMPONENT 1 INPUT,COMPONENT2INPUT, S-VIDEO INPUT, TUNER,VIDEO OUTPUT (Audio In : 0.4Vrms, over 10KVideo In : 1Vp-p, over 75)

Sound output
10W+10Wrms Stereo (Max)

Part appearance

ADJUSTMENT INSTRUCTION WITH DEFAULT FACTORY DATA

Service mode data adjustment

When the EEPROM has been replaced, the SVC data should be restored as the function of individual system and specification.
When the EEPROM has been replaced White Blance Checking.

Enter and exit SVC mode.  Into the SVC mode, Initialize with default data.
1) Press 5 Seconds MENU buttons on both TV set and Remote Controller at the same time to get into SVC mode.
2) Press the PR ▲▼ button several times to find SVC Data.
3) Input the corresponding SVC data referring to Table below with the VOL
◀▶ , key.
4) Press TV/AV button to exit SVC mode.

White balance checking



Circuit diagram [Schematic]

The TFT LCD TV described in the followings is based on a Multi TV system, digital Control display, 23.01" diagonal. The TFT LCD TV is intended to be a finished product, Basically a display device mounted inside an enclosure which will provide the safety Requirements. With the exception of LCD Panel, the display device shall be composed entirely of solid state components.
These components shall have a history of reliable service in identity applications and shall be applied in the circuits.

SCALER SECTION.
VCT 49xxi SECTION.
Video A/D Converter

The MST6151 is a high performance and fully integrated graphics processing IC solution for multi-function LCD monitor/TV with resolutions up to SXGA/WXGA. It is configured with an integrated triple-ADC/PLL, an integrated DVI/HDCP receiver, a video de-interlacer, two high quality scaling engines, an on-screen display controller, and a built-in output clock generator. By use of external frame buffer, PIP is provided for multimedia applications. It
supports de-interlaced full-screen video, video-on-graphic overlay, video-by-graphic split screen, frame rate conversion, and aspect ratio conversion for various video sources. To further reduce system costs, the MST6151 also integrates intelligent power management control capability for green-mode requirements and spread-spectrum support for EMI management.

The VCT 49xxI is an IC family of high-quality singlechip TV processors. Modular design and deep-submicron technology allow the economic integration of features in all classes of singlescan TV sets. The VCT 49xxI family is based on functional blocks contained and approved in existing products like DRX 396xA, MSP 34x5G, VSP 94x7B, DDP 3315C and SDA 55xx.
Each member of the family contains the entire IF, audio, video, display, and deflection processing for 4:3 and 16:9 50/60-Hz mono and stereo TV sets. The integrated microcontroller is supported by a powerful OSD generator with integrated Teletext & CC acquisition including on-chip page memory.

Video A/D Converter

Most flat-panel monitors and projectors require a digital graphics input in order to accurately scale and display graphics. The huge installed base of computers with analog video graphics interfaces necessitates the use of a graphics digitizer to re-digitize the analogue RGB signal before further processing.
■ The MST9883CR is a fully integrated analog interface for digitizing high-resolution RGB graphics signals from PC’s and workstations. With a sampling rate capability of up to 140 MHz, it can accurately support display resolutions up to 1280x1024 (SXGA) at 75 Hz. The clamped input circuits provide sufficient band width to accurately digitize each pixel.
■ The MST9883CR provides a high performance highly integrated solution to support the digitization process, including the ADC’s, a voltage reference, a PLL to generate the pixel sampling clock from HSYNC, clamping circuits, and programmable offset and gain circuits to provide brightness and contrast controls.
■ When the COAST signal is asserted, the PLL will maintain its output frequency when HSYNC pulses are absent, such as during the VSYNC period in some systems.
■ A 32-step programmable phase adjustment control (0-360 deg) is provided for the pixel sampling clock to adjust for the difference between the HSYNC edge and RGB pixel edge timing.
■ The MST9883CR can send output data through one 24-bit port at the pixel clock rate.
■ The MST9883CR can also support RGB to YCbCr conversion.
■ The MST9883CR has internal programmable pattern generator for testing.
■ The MST9883CR can accept either standard TTL, CMOS levels or saw tooth vertical deflection signals for VSYNC input.

Wednesday, 3 February 2021

Daewoo DTA20, DTA21, DTE25, DTE28 - using IC TDA9367, STR F6653, using IC TDA9365, STR F6653 - How to enter the service mode

 

ATSS sorting method: The TV set sweeps all the TV bands from beginning of VHF to end of UHF. The TV controlling software for each program checks if a VPS CNI code is transmitted. If no VPS CNI code is found, the system check if a CNI code is transmitted in the teletext lines ( Packet 8/30 format 1 ). If such a code ( VPS or teletext ) is found and if this code is in the ATSS list, the program is automatically named.
The programs found are then sorted in 4 groups

Group I : It contains all the programs from the selected country and named by the TV controlling software. Within this group the sorting order is fixed by the ATSS list.
Group II : It contains all the programs with a strong signal strength which are not listed in group I.
Group III : It contains all the programs with a weak signal strength which are not listed in group I.
Group IV : If two or more programs with the same code are found, only the strongest ( or if they have the same level the one with the lowest frequency) is listed in group I, II or III. The others are listed in group IV.

Note : If two programs with the same name but a different code are found these two programs are listed in group I, II or III ( e.g. Regional program SW3 in Germany ).

The sorting order within group II, III, and IV is based on the channel frequency. The program with the lowest frequency is allocated the first rank in its group, and so forth until the last program of the group which has the highest frequency.

Special case : Country selection =  Others

Special case : France
If France is selected the TV controlling software sweeps the whole TV bands firstly with France system selected ( positive video modulation) and secondly with Europe system selected ( negative video modulation).

Special case : Switzerland
If Switzerland is selected the TV controlling software sweeps the whole TV bands firstly with Europe system selected (negative video modulation) and secondly with France system selected ( positive video modulation).

Special case : GB
Note for satellite receiver users : Before starting ATSS turn On your satellite receiver and tune “ SKY NEWS “.
If GB is selected the TV controlling software seeks for programs only in UHF ( C21 to C70 ). The sorting order is :
1 - BBC1
2 - BBC2
3 - ITV
4 - CH4
5 - CH5
6 – NEWS

If two or more “ identical “programs ( same name but different code e.g. BBC1 and BBC1 Scotland ) are found the following programs in the list will be shifted up. (1 - BBC1, 2 - BBC1, 3 - BBC2, 4 - ITV, 5 - CH4, 6 - CH5, 7 - NEWS, ..)

If one of the program above is not found, the associated program number remains empty ( freq.=467.25
Mhz - Skip selected - no name - system=GB).
example A : 1 - BBC1, 2 - BBC2, 3 - ITV, 4 - -----, 5 - CH5, 6 - NEWS, ...
example B ( if 2 BBC1 found ) : 1 - BBC1, 2 - BBC1, 3 - BBC2, 4 - ITV, 5 - -----, 6 - CH5, 7 - NEWS, ...

Alignment

Microcontroller configuration : Service mode
To switch the TV set into service mode please see instruction below.

1 - Select pr. number 91
2 - Adjust sharpness to minimum and exit all menu.
3 - Quickly press the key sequence :
RED - GREEN – menu

To exit SERVICE menu press menu key or Std By key.

In Service Mode press “OK” to stop the microcontroller i.e. the I2C bus is free and the set can be controlled by external equipment. Press “OK” again to allow the microcontroller to control the set again.

Data Capture: The Data Capture section takes in the analogue Composite Vidéo and Blanking Signal (CVBS), and from this extracts the required data, which is then decoded and stored in memory.

The extraction of the data is performed in the digital domain. The first stage is to convert the analogue CVBS signal into a digital form. This is done using an ADC sampling at 12MHz. The data and clock recovery is then performed by a Multi-Rate Video Input Processor (MuIVIP). From the recovered data and clock the following data types are extracted WST Teletext (625/525), Closed Caption, VPS, WSS.
The extracted data is stored in either memory (DRAM) via the Memory Interface or in SFR locations.

TDA894xJ Stereo Audio Amplifier

The TDA 8944J ( TDA 8946J ) is a dual-channel audio power amplifier with an output power of 2 x 7 W ( 2 x 15 W ) at an 8 W load and a 12 V supply. The circuit contains two Bridges Tied Load (BTL) amplifiers with an all-NPN output stage and standby/mute logic. The TDA8944J comes in a 17-pin DIL power package.

Daewoo schematic using IC TDA9365, STR F6653

Daewoo schematic using IC TDA9367, STR F6653


LG 52LG50FD, 52LG50FD-SA-Service adjustments-service mode entry-white balance adjustment-ADC component 1 RGB adjustment and more

  These adjustments are similar to 42LB7DF Because this is not a hot chassis, it is not necessary to use an isolation transformer. However...