How to disassemble LG DM19D mechanism – LG OK75

 LG DM19D - LG OK75 - mechanism disassemble procedure

Cover Top
1) Remove the 2 screws (S1).
2) Remove the Cover Top.

Clamp Assembly
1) Place the Clamp Assembly as Figure B.
2) Bending the Cover Top in direction of arrow (2) as Figure B.
3) Separate the Clamp Assembly from the
Cover Top.

 Plate
1) Turn the Plate to a counterclockwise direction
and then lift up the Plate.
2) Remove the Plate.
Magnet
Remove the Magnet.
Clamp
Remove the Clamp.

Tray Disc
1) Insert and push a flat-head screwdriver in the Emergency eject hole (H1) at the right side, so that the Tray Disc is ejected about 15 ~ 20 mm.
2) Pull the Tray Disc until it is locked.

3) Grasp the both sides of the Tray Disc and lift it up as Figure D, and then pull the Tray Disc until it is separated from the MD Sub Assembly completely.

Pick Up Assembly
1) Detach the Gasket Tape.
2) Disconnect the wires (BLK, RED, BRN, ORN) from the Deck PCB Assembly by desoldering.
3) Remove the 4 screws (S2).
4) Disconnect the FFC Cable from the Pick Up Assembly.
5) Remove the 4 Rubber Dampers.

Base Up-Down
Unlock the Locking Tab (L2) in direction of arrow and then lift up the Base Up/Down to separate it from the Base Main.

• When reassembling move the Guide in direction of arrow (A) until it is positioned as Figure G-1.
• When reassembling insert the (B) portion of the Base Up/Down in the (C) portion of the Guide as Figure G-2.
• When reassembling insert the (D) portion of the Base Up/Down in the Hole (H2) of the Base Main as Figure G-3.

Belt Loading
Remove the Belt Loading.
Gear Pulley
Unlock the Locking Tab (L3) in direction of arrow and then separate the Gear Pulley from the Base Main.
Gear Loading
Remove the Gear Loading.
Guide
1) Move the Guide in direction of arrow (A) as Figure H-1.
2) Separate the Guide from the Base Main.

Deck PCB Assembly
1) Disconnect the wires (RED, BK) form the Deck PCB Assembly by desoldering.
2) Remove the 1 screw (S3).
3) Separate the Deck PCB Assembly from the Base Main.
Motor Assembly
Unlock the Locking Tab (L4) in direction of
arrow and then separate the Motor Assembly
from the Base Main.
FFC Cable
Remove the FFC Cable.

DM19D Exploded view

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 10KΩ Video In : 1Vp-p, over 75Ω)

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.

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

MACKIE DL806 - DL1608 wireless digital mixer-assembly-wiring diagram

 

General Digital
Sample Rate: 48 kHz
A/D/A Bit Depth: 24-bit
System Latency: 1.5 ms

Frequency Response
All inputs to all outputs: ±0, –1 dB, 20 Hz to 20 kHz

Mic input to Main Output (A–weighted)
Channel and main faders at unity: –79 dBu
Faders down: –90 dBu

Dynamic Range (One channel and main fader at unity, A–weighted): 109 dB

CMRR: >70 dB @1 kHz (60 dB gain)

Analog Inputs 1–16

1-12: XLR Balanced

13-16: Combo XLR / TRS Balanced

Supported Devices
iOS Version Requirement: iOS 5.1 or higher [Master Fader] iOS 6 or higher [My Fader]

DL Series mixer with Lightning Connector

Wired:  iPad(4th generation), iPad mini (With iPad mini tray accessory)

Wireless:  All iPad models, iPhone (iPhone 4, iPhone 4S and iPhone5), iPod touch (4th and 5th generation)

DL Series mixer with 30-pin Connector

Wired:  Original iPad, iPad 2, iPad (3rd generation)

Wireless:  All iPad models.

Control Application: Mackie Master Fader App, Mackie My Fader App

External Supply Power Requirements: 100-240 VAC, 50-60 Hz, Universal Supply, Output Voltage:  12 VDC, Current:  4A, DC Connector:  5.5 mm x 2.5 mm barrel with locking ring

Line Cord:  User-replaceable IEC. Power Consumption:  48 W max. Weight: 6.9 lb / 3.1 kg

Service Kits
• 30-PIN CONNECTOR WITH TRAY SERVICE KIT (Includes instructions) PN#2039264
• 30-PIN DOCK SERVICE KIT (Includes instructions) PN#2042301
• LIGHTNING CONNECTOR WITH TRAY SERVICE KIT (Includes instructions) PN#2039276
• LIGHTNING DOCK SERVICE KIT (Includes instructions) PN#2042300
• DL iPAD MINI TRAY KIT (Includes instructions) PN#2042302

Block diagram

Assembly and quick parts

Wiring diagram

Bottom side and top side of the PWB

Below is an annotated picture of DL1608 and DL806 showing how the channels are named in the hardware (since variations between models are by board no-stuffs, and the same physical channels are not labeled the same between models for the user). So the schematics, and connector pin-out documentation, use these labels as appropriate. H/W inputs A5-A8 are combo jacks. All others are regular XLR

Samsung LCD TV Monitor LT20A350-troubleshooting, factory mode and service mode

 

Samsung LT22A350, LT23A350, LT24A350, LT20A350, LT22A550, LT23A550, LT24A550, LT27A550.  Chassis: WDS2, WDS4

  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.

Leakage Current Test

With the unit completely reassembled, plug the AC line cord directly into a 120V AC outlet. With the unit’s AC switch first in the ON position and then OFF, measure the current between a known earth ground (metal water pipe, conduit, etc.) and all exposed metal parts, including: metal cabinets, screwheads and control shafts.
The current measured should not exceed 0.5 milliamp.
Reverse the power-plug prongs in the AC outlet and repeat the test.

Troubleshooting

No Power

- The LEDs on the front panel do not work when connecting the power cord.
- The SMPS relay does not work when connecting the power cord.
- The units appears to be dead.

The IP relay or the LEDs on the front panel does not work when connecting the power cord if the cables are
improperly connected or the Main Board or SMPS is not functioning. In this case, check the following:
- Check the internal cable connection status inside the unit.
- Check the fuses of each part.
- Check the output voltage of SMPS.
- Replace the Main Board.

No Video (Analog PC signal)

- Check the PC source
- Check the Arsenal, Check the Main Chipset.
- This may happen when the LVDS cable connecting the Main Board and the Panel is disconnected.

No video (HDMI 1, 2, 3, 4 - Digital signal)

Audio is normal but no picture is displayed on the screen.

- Check the HDMI source.
- Check the HDMI switch, Check the Main Chipset.
- This may happen when the LVDS cable connecting the Main Board and the Panel is disconnected.

No Video (Tuner_CVBS)

- Audio is normal but no picture is displayed on the screen.

- Check the Tuner CVBS source.
- Check the Tuner, Check the Main Chipset.
- This may happen when the LVDS cable connecting the Main Board and the Panel is disconnected.

No Video (Tuner DTV)

- Audio is normal but no picture is displayed on the screen.

- Check the DTV source.
- Check the Tuner, Check the Main Chipset.
- This may happen when the LVDS cable connecting the Main Board and the Panel is disconnected.

No Video (Video CVBS)

- Audio is normal but no picture is displayed on the screen.

- Check the Video CVBS source
- Check the Main Chipset.
- This may happen when the LVDS cable connecting the Main Board and the Panel is disconnected.

No Video (Component)

- Audio is normal but no picture is displayed on the screen.

- Check the Component source
- Check the Main Chipset.
- This may happen when the LVDS cable connecting the Main Board and the Panel is disconnected

No Sound

- Video is normal but there is no sound..

- When the speaker connectors are disconnected or damaged.
- When the sound processing part of the Main Board is not functioning.
- Speaker defect.

Entering Factory Mode

To enter ‘Service Mode’ Press the remote -control keys in this sequence :
- If you do not have Factory remote – control.

Power Off > Info > Menu > Mute

How to Access Service Mode

Using the Customer Remote
1. Turn the power off and set to stand-by mode.
2. Press the remote buttons in this order; POWER OFF- INFO - MENU - MUTE to turn the set on.
3. The set turns on and enters service mode. This may take approximately 20 seconds.
4. Press the Power button to exit and store data in memory.
- If you fail to enter service mode, repeat steps 1 and 2 above.
5. Initial SERVICE MODE DISPLAY State.

x How to enter the hidden factory mode.
a. into the factory mode
b. move the tap to Advanced
c. key input : 0 + 0 + 0 + 0
xx hidden menu : Advanced

Buttons operations within Service Mode

Lenoxx MC 261 schematic, exploded view, wiring diagram and Lennox MC242CD SCHEMATIC

 

Do the following safety checks after servicing this unit.

1. Remove all the externally connected test equipment and wires before testing the unit.
2. Use the safety test circuit as shown below.
3. Plug the power cord or unit to be tested into the test receptacle.
4. Switch the unit being tested to ON or PLAY.
5. Connect external jack/terminal contact VTVM across a 1k resistor in the test circuit. Set the meter to a high (150V AC) scale to avoid meter damage and then touch the points with the test probe.  If the meter reading indicates less than 3 volts on all test points, set the meter to a low (3V AC) scale and repeat the test.
6. Any reading greater than 0.2 volt indicates a potential shock hazard. If this occurs, determine the cause of the leakage, correct the problem, and repeat the safety test.

  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.

Wiring diagram

Schematic diagram

Exploded view

Exploded view

Lenoxx MC-242 CD schematic

BN44 00285A and SS 9002A POWER SUPPLY SCHEMATIC

 

BN44 00285A – H32F1-DY POWER – STR W6252, FAN7530, BD9893F

SS 9002A Power supply schematic