LG RF-21FB20R, LG RT-21FB20R - 21 inch CRT TV – Service mode, option adjust, circuit diagram

LG RF/RT-21FB20R/RE/RQ/RX/RW, RF/RT-21FB20V/VE/VG/VQ/VW - MC-019A CHASSIS 

 Used ICs: LA7016, TDA9361/81/70, MSP34100, TDA9859, TDA6107Q, STR-F6654R, LA7840 

Adjustments

Test Equipment required
1. Multimeter (volt meter)
2. Oscilloscope
3. 10:1 PROBE
4. Color Analyzer

CDL Data Adjustment(LINE SVC-0)
1) Press the SVC button to get into the SVC-0 Mode.
2) Press the Channel UP/DOWN button to select CDL12.
3) Press the Volume UP/DOWN button until the CDL data is the same as the Table below.

4) Press the OK(i) button to memorize the data.

OPTION Data Adjustment(OPTION-1,OPTION-2)
1) Press OK buttons on both TV set and Remote Controller at the same time to get into SVC mode.
2) Press the Yellow button several times to find OPTION-1 or OPTION-2.
3) Input the correspond OPTION data referring to Table below with the numeric buttons.
4) Press the OK(¡) button to memorize the data.

Screen Voltage Adjustment

1) Connect the probe of oscilloscope to the RK (Red Cathode) of CPT Board.

2) Set the oscilloscope to 50V/div and 20Us/div and after putting GND line upon the lowest grid line of the scope by pressing GND button, enter into DC mode.
3) Tune the TV set to receive a PAL-B/G 05CH.
4) Adjust Screen Volume of FBT so that the waveform is the same as below.

White Balance Adjustment.(LINE SVC-0)

This adjustment should be performed after screen voltage adjustment.
1) Tune the TV set to receive an 100% white pattern.
2) Press OK(¡) buttons on TV set and remote controller at the same time to get into SVC mode.
3) Press Yellow button on remote controller. (Standard mode)
4) Press Channel UP/DOWN button for desirous function adjustment.
5) Adjust VOL+ or VOL-button in each status of "RG--"/"BG--" for
X=272¡ 8, Y=288¡ 8 with color analyzer.

(Europe Model: X=288¡ 8, Y=295¡ X=272¡ 8, 11,000K)

Schematic [Full]

Power and Deflection section

Deflection Adjustment Procedure
VL (Vertical Linearity)
Adjust so that the boundary line between upper and lower half is in accord with geometric horizontal center of the CPT.
VA (Vertical Amplitude)
Adjust so that the circle of a digital circle pattern may be located within the effective screen of the CPT.
SC (Vertical “S” Correction)
Adjust so that all distance between each horizontal lines are to be the same.
VS (Vertical Shift)
Adjust so that the horizontal center line of a digital circle pattern is in accord with geometric horizontal center of the CPT.
HS (Horizontal Shift)
Adjust so that the vertical center line of a digital circle pattern is in accord with geometric vertical center of the CPT.
Press the OK(¡) button to memorize the data.

Convergence Adjustment

This procedure DOES NOT apply to bonded yoke and picture tube assemblies.
Do not use screen magnets during this adjustment procedure. Use of screen magnets will cause an incorrect display.

Philips 46PFL3706-F7 – LCD TV – Power board schematic, service mode, firmware update, Initialization

                    Philips 46" LCD TV

Electrical adjustments are required after replacing circuit components and certain mechanical parts. It is important to perform these adjustments only after all repairs and replacements have been completed.  Also, do not attempt these adjustments unless the proper equipment is available.

Test Equipment Required

1. Remote control unit
2. Color Analyzer,
CA-310 (KONICA MINOLTA Luminance meter) or measuring instrument as good as CA-310.

How to set up the service mode

1. Turn the power on.
2. Press [MENU] button to display Setup menu.
3. Select “Features”.
4. Select “Current Software Info”.
5. Press [0], [6], [2], [5], [9], [6] and [INFO] buttons on the remote control unit in this order. The service mode screen appears.

Purity Check Mode
This mode cycles through full-screen displays of red, green, blue, and white to check for non-active pixels.
1. Enter the service mode.
2. Each time the [7] button on the remote control unit is pressed, the display changes as follows.

3. To cancel or to exit from the Purity Check Mode, press [PREV CH] button.

The White Balance Adjustment should be performed when replacing the LCD Panel or Digital Main CBA.

Symptom of Misadjustment: White becomes bluish or reddish.

1.Operate the unit for more than 60 minutes.
2. Enter the service mode.
3. Press [VOL - ] button three times on the remote control unit to select “Drive setting” mode. “Drive” appears in the screen.
4. Set the color analyzer at the CHROMA mode and zero point calibration. Bring the optical receptor pointing at the center of the LCD-Panel.

Note: The optical receptor must be set perpendicularly to the LCD Panel surface.
5. Press [3] button to select the “HDB” for High Drive Blue adjustment. (“HDB” appears in the screen.)

6. Press [MENU] button. The internal Raster signal appears in the screen. (“Internal (Single)” appears in the upper right of the screen as shown below.)

7. Press [CH + or -] buttons to adjust the color temperature becomes 12000°K (x= 0.272 / y= 0.278 ±0.002).
8. Press [1] button to select the “HDR” for High Drive Red adjustment (“HDR” appears in the screen.) and press [CH + or -] buttons to adjust the color temperature.
9. If necessary, adjust the “HDB” or “HDR” again.
10. Press [6] button to select the “LDB” for Low Drive Blue adjustment (“LDB” appears in the screen.) and press [CH + or -] buttons to adjust the color temperature.

11. Press [4] button to select the “LDR” for Low Drive Red adjustment (“LDR” appears in the screen.) and press [CH + or -] buttons to adjust the color temperature.
12. If necessary, adjust the “LDB” or “LDR” again.
13. Press [VOL -] button to shift to the “Debugging Message” mode.  If there is no message under “[WB]” section, this adjustment completes.
If “Drive settings are NG. Retry.” is displayed, repeat above steps from 5. to 12. Then check “Debugging Message” again. If “Drive settings are NG. Retry.” is displayed, replace the LCD Panel or Digital Main CBA.
14. To cancel or to exit from the White Balance Adjustment, press [PREV CH] button.

SMPS schematic [Circuit diagram] and PWB

Fixed voltage (or Auto voltage selectable) power supply circuit is used in this unit.  If Main Fuse (F1601) is blown , check to see that all components in the power supply circuit are not defective before you connect the AC plug to the AC power supply. Otherwise it may cause some components in the power supply circuit to fail.

For continued protection against risk of fire, replace only with same type 4A, 250V fuse.

TO INITIALIZE THE LCD TV

Initialization is to place the set in a new out of box condition. The customer will be prompted to select a language and program channels after the set has been initialized.
To put the program back at the factory-default, initialize the LCD TV using the following procedure.

1. Turn the power on.
2. Enter the service mode.
 [To cancel the service mode, press [Power] button on the remote control unit.]
3. Press [FREEZE] button on the remote control unit to initialize the LCD television.
4. "INITIALIZED" will appear in the upper right of the screen. "INITIALIZED" color will change to green from red when initialization is completed.

FIRMWARE RENEWAL

There are two states (the User Upgrade and the Factory Upgrade) in firmware update.

The identification of User Upgrade and Factory Upgrade are done by the filename.
1. Turn the power off and unplug the AC Cord.
2. Insert the USB storage device to the USB port.

3. Plug the AC cord in the wall outlet and turn the power on.

4. The update will start and the relative screen will appear.

[If the above screen isn’t displayed, repeat from step 1]

5. When the firmware update is completed the finished screen will appear.

“The software upgrade is completed.
Remove USB storage device, turn TV off then on again”

When the Factory Upgrade is used, after restarting TV, shift to initial screen menu in service mode. "INITIALIZED" will appear in the upper right of the screen. "INITIALIZED" color will change to green from red when initializing is completed.

LG CM2630B Hi-Fi system - power board circuit diagram, program download, troubleshooting

LG CM2630B (CM2630B, CMS2630FH) Micro Hi-Fi System – SMPS schematic, troubleshooting, program download

PROGRAM DOWNLOAD

AUDIO PROGRAM
Download program file name must be CM2630_YYMMDDX.HEX
If security program (Water Wall) is activated on PC, you must save the file to the USB storage device and disable the security software, then download the file to your set.
Caution: When downloading the file, you should neither unplug the USB device, change to the other function, nor power off the device. USB device must be unplugged when the downloading process is completed.

CD PROGRAM
Download program file name must be HF000_CM2630_YYMMDDX.bin
If security program (Water Wall) is activated on PC, you must save the file to the USB storage device and disable the security software, then download the file to your set.
Caution: When downloading the file, you should neither unplug the USB device, change to the other function, nor power off the device. USB device must be unplugged when the downloading process is completed.

TOUCH PROGRAM

Download program file name must be TC380_LG_CM2630_YYMMDDX.DLD
If security program (Water Wall) is activated on PC, you must save the file to the USB storage device and disable the security software, then download the file to your set.
Caution: When downloading the file, you should neither unplug the USB device, change to the other function, nor power off the device. USB device must be unplugged when the downloading process is completed.

EQ PROGRAM
Download program file name must be EQ_PRG.BIN
If security program (Water Wall) is activated on PC, you must save the file to the USB storage device and disable the security software, then download the file to your set.
Caution: When downloading the file, you should neither unplug the USB device, change to the other function, nor power off the device. USB device must be unplugged when the downloading process is completed.

LG CM2630B SMPS schematic

DC-DC converter

LG CM2630B Power amplifier schematic

NO POWER PROBLEM
No power problem occurs when you power on the unit.
Solution
Replace X100, IC101, IC103.
How to troubleshoot (Countermeasure)
1) Check X100 (Crystal).
Ö If it does not oscillate, change X100.
2) Check IC103 (Reset IC).
Ö If its output voltage is not more than +2.7 V, change IC103.
3) Check IC101 (Micom).
Ö After power is on if the pin8 of IC101 is not ‘High’, change IC101.
But, the new μ-com IC need to write program.

SPEAKER NO AUDIO OUTPUT

No audio output problem occurs when you power on the unit.
Solution
Replace IC700.
How to troubleshoot (Countermeasure)
1) Check IC700 Pin1(VCC_12 V) for driving the gate of IC700 (AMP IC).
a. If +12 V is low, there is possible for AMP IC to be damaged.
b. Remove bead among L700, L703.
When removed bead, if +12 V is recovered, the IC connected to it was damaged.
c. Replace the IC with a new one.
2) Check the impedance between AMP PWM output & GND.
a. If the impedance is about 0 Ω, the IC must be damaged.
b. Replace it with a new one (AMP IC).

USB NO OUTPUT
When USB insert, USB no detect on the unit.
Solution
Replace IC902.
How to troubleshoot (Countermeasure)
1) Please check Harness connection between Main(CN103) and Top(CN370) BD.
2) If it is OK, please check two ICs below.
3) Please check IC902 of Main BD.
Ö Pin2 : 12 V, L907 : 5.6 V
4) Please check IC362 of TOP BD.
Ö Pin2 : 5.6 V, Pin3 : 5 V
5) If it is not OK, replace IC902 or IC362.

NO BOOTING
After you turn on the unit and displayed message in the following order (HELLO > VOL XX > CD or USB...etc) on LCD, it will not display other message on LCD, and it will not boot-up normally.
Solution
Replace X500.
How to troubleshoot (Countermeasure)
1) Please check the soldering status of 12 MHz crystal (X500).
2) Please check the frequency of 12 MHz crystal (X500).
3) If the crystal doesn’t oscillate, replace X500.
4) After changing it, if the set is still not booting, replace MAIN board assembly.

How to enter the service mode – Daewoo DTX21G2 color TV - schematic – service adjustments

Daewoo DTX-21G2, DTX-21B4, DTX-21U7 COLOR Television CHASSIS: Model: CP-520V – Used ICs STR-W6754, TDA12020H1/N1 FO1 UOCIII- Hercules, LTC-565 FBT

MICRO-CONTROLLER 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 menus.
3  Within 2 seconds press the key sequence : RED - GREEN – menu

The software version is displayed beside the word Service, e.g. “SERVICE VER 1.46”.
To exit SERVICE menu press menu key or Std By key.

SERVICE MODE NAVIGATION
Pr Up/Down remote keys : cycle through the service items available.

Vol -/+ remote keys: Dec./Increment the values within range – Cycle trough option bits

OK key: Toggle bits in option byte.

MICROCONTROLLER CONFIGURATION: OPTION BITS

There are two option bytes available (16 bits in all). These option bits are available from Service mode. First find the OPTION1 or OPTION2 control, and then use the Volume PLUS/MINUS buttons on the remote control keypad to locate the bits, and OK key to toggle them. 

NVM default setting

The purpose of this message, when you change a virgin EEPROM, is to allow to modify the NVM DATA to desired values.

The NVM default valus are fixed for the user, but for flexibility in service, these data are stored in NVM and can be changed when the TV set is in a special mode call "NVM EDITOR". This mode can only be access from "FACTORY" mode.

Entering into "FACTORY" mode.
To switch the TV set into FACTORY mode, use the factory remote control, and press on “SVC” key. The factory menu will appear on the screen, showing “FACTORY” , plus other relevant information like software version and date.
WARNING : When in "FACTORY" mode you should not press any key other than the keys described in the procedure below. Unwanted key stroke could misadjust the TV set.

Entering into "NVM EDITOR" mode.
To switch the TV set into NVM EDITOR mode, use the user remote control, and press on “PICTURE/OK” key. The NVM EDITOR window will appear on the screen. This mode allow you to access all data stored in NVM. The current NVM address is given in column "ADDR." in both DECimal and HEXadecimal format. The column DATA gives the value contained at selected address in both DECimal and HEXadecimal format.

Navigation in "NVM EDITOR" mode.
Use Program Up/Dwn keys to select the desired address. Use Volume Up/Dwn keys to change the data at selected address. You must press "PICTURE/OK" key to store value after modification.

[The data can be adjusted between 0 and 63]

Exit "NVM EDITOR" mode.

To switch the TV set back into FACTORY mode, use the user remote control, and press on “MENU” key.
The factory menu will appear on the screen, showing “FACTORY”.

Exit "FACTORY" mode.
To exit "FACTORY" mode, use the factory remote control, and press on “SVC” key.
The factory menu will disappear from the screen.

NVM DATA CHANGE LIST

TV SET ALIGNMENT

G2 ALIGNMENT

- Tune a colour bar pattern.
- Find the “G2 – SCREEN” item in service mode.
- Adjust screen volume (on FBT) to bring the cursor to central position(Green).

WHITE BALANCE
- Select a dark picture and adjust RED BIAS and GRN BIAS to the desired colour temperature.
- Select a bright picture and adjust RED, GRN and BLUE GAIN to the desired colour temperature.

FOCUS
Adjust the Focus volume (on FBT) to have the best resolution on screen.

VERTICAL GEOMETRY
Adjust V. LINEAR (linearity), S CORRECT (S. Correction), VERT SIZE (Vertical amplitude), VERT CENT (vertical centering) to compensate for vertical distortion.

HORIZONTAL PICTURE CENTRING
Adjust HOR CEN (Horizontal center) to have the picture in the center of the screen.

AGC
 Make sure option bits are correct for the tuner fitted on the chassis (See above how to change option bits).
 Adjust the antenna signal level at 62 dBmV
 Tune a colour bar pattern.
 Find the “AGC” item in service mode.
 Press the key “OK” on the remote keypad and wait until AGC level stabilize to the optimum value.
 Alternatively, use “Vol Up/Dwn” keys to adjust manually to the desired Tuner Take Over Point (TOP).

Circuit diagram and PWB

Click on the pictures to magnify

Working principle and general troubleshooting – Philips L05HD NTSC CRT TV

When troubleshooting the set, the defective panel requiring replacement or additional repair must be located. The Power supplies, Deflection, 1fH inputs, and Audio outputs are located on the Family board. The 2fH, CRT drive, and Deflection drive circuits are located on the Trident board.
If the set turns ON without a picture or sound, first check the power supplies located on the Family board. If the set comes ON, then shuts Off, there may be a problem with the shutdown circuits which are located on the Family board. If the picture is missing, but sound and high voltage are present, the problem may be located on the Trident panel.

TV Signal Processor

Red, Green, and Blue from the Trident IC is input on Pins 30, 31, and 32 of 7221, TV Display Processor. The RGB/YUV matrix changes the signal to a YUV signal before feeding it to a Color level control circuit. The signal is fed to the RGB insertion circuits where the OSD is inserted. The signal is then fed to a White Point and Brightness Control circuit and then to the CRT panel. The White Point and Output Amplifier have the Drive controls and Cutoff controls. Input from the ABL line on Pin 43 makes adjustments in the brightness levels to adjust for changes in beam current. The Cutoff pulses from the CRTs are fed to Pin 44 to the Cathode Calibration circuit. The Cathode Calibration circuit adjusts the cutoff levels of the CRT to maintain the correct gray scale tracking. 

When the set is first turned On, a calibration pulse is output on the RGB lines. The Cathode Calibration circuit monitors this pulse on the Cutoff line to set the Black level and the maximum drive voltage for the cathode. Once the Calibration has taken place, the Output Amplifier switches to the RGB drive signal as the output. Horizontal and Vertical Sync is fed to 7600 on Pins 23 and 24. IC 7600 processes the sync to provide the geometry for the picture. Horizontal drive is output to the sweep circuit on Pin 8. Vertical drive is output on Pins 1and 2. East West drive is output on Pin 3. Sandcastle (SCO) is output on Pin 9. Horizontal Feedback (HFB) from the sweep circuit is fed into the Phase Loop to phase correct the Horizontal drive. IC 7221 is controlled by the Hercules Processor on the Family Board via the I2C buss on Pins 10 and 11. Transistors 7226 and 7227 levels shifts the I2C buss level between 5 and 3.3 volts. Geometry and Drive settings are stored in the Memory IC located on the Family Board.

Deflection: Sync

Whatever signal is applied to the L05 chassis, it will display the picture in a 1080i format. This means that the Line or Horizontal frequency is always 33.75 kHz. The Vertical or Frame rate is 60 Hz.
Vertical Sync is output from the Trident IC 7201 on Pin 35. The signal is buffered by Transistor 7203 before being fed to the TV display processor and TV Microcontroller. In the same manner Horizontal Sync is output on Pin 34 and is buffered by Transistor 7204.

Synchronization section circuit

Deflection

Horizontal drive from 7221 is fed to Transistor 7404 located on the Family board. This drive circuit has two power sources. During startup, it is powered by the +6 volt supply. Once the High Voltage circuit is running, it is powered by Pin 9 of the IFT. 7404 drives Transformer 5402 which drives the HOT (Horizontal Output Transistor). The HOT drives the IFT and the Horizontal Deflection Coil. The IFT is powered by the VBAT (141 volt) supply.
The IFT produces High voltage, Focus voltage and G2 voltage to drive the CRT. In addition, a 200 volt supply is produced to drive the CRT panel, a +14 and -14 volt supply for the Vertical output, Filament voltage, +200 volt VideoSupply, and a +12V_lot supply.
Transistor 7408 monitors the IFT secondary to sense the presence of over voltage. If the High Voltage goes High, the voltage on Pin 6 of the IFT will go High. When the voltage on diode 6480 exceeds 15 volts, transistor 7408 will turn On. If 7408 turns On, it will turn 7407 On causing the x_ray protect line to go Low. The Processor will then shut the set down. In addition the EW_DRIVE circuit is monitored. If the EW_DRIVE fails, transistor 7406 will turn On constantly placing a dc voltage on the source. This will turn 7407 On. IC 7451 is the Vertical Output IC. It is powered by the +14 and -14 volt supply from the IFT.
The Vertical pulse is rectified by 6458, keeping the V_PROTN line High. If the vertical output should fail, the V_PROTN line will go Low. The Hercules processor will then shut the set down.

Line-Frame deflection

Set Control

The L05HD has two microprocessors, The Hercules located on the Family board and the TV Controller located on the Trident board.

The Hercules, 7200, provides control for the entire set. During standby, the Hercules and the Remote sensor are powered by the 3.3 volt supply. The customer communicates with the Hercules via the Remote sensor and Power switch located on the Front Control panel. The power supplies are switched On via the STBY-CONT and B lines. The TV Controller is reset by the C control line. The I2C bus communicates with the EEPROM 7601, Tuner 1000, TV Controller 7206, Trident 7201, A/D 7210, TV Display Processor, 7221, and HDMI panel.

Hercules Processor

Signal flow

The output of the Tuner is fed to the SAW filter, 1002, and then to 7200, Hercules, on Pins 104 and 105. The SVHS (YC) signals are combined inside 7200. IC 7200 selects between AV1, AV2, Side, and Tuner composite video. The selected composite video is output on Pin 65. Video buffered by Transistor 7211 is fed to IC 7206 located on the Trident panel which extracts Closed Caption text and Teletext information. This IC also generates the OSD (On Screen Display). Video buffered by 7212 is fed to the Trident IC which has an internal 3-D Comb Filter and A/D converter. IC 7201 rescales the picture to 1080i.
Component video is inserted into the YPbPr input located on the Family board. The HDMI panel converts the HDMI signal into an analog YPbPr format. Both of these signals are fed to the Switch, 7205 which selects between the two. The selected signal is fed to IC 7210 which performs an A/D conversion. This 24 bit signal is fed to 7201. The Scaler (Trident IC) converts the signal to a 1080i format as well as performing picture enhancement functions.
DRAM ICs 7215, 7216, 7217, and 7218 stores picture data for the Scaler as it is being processed. And internal D/A conversion circuit outputs the 1080i signal is an RGB format on Pins 27, 28 and 29. Horizontal and Vertical sync is output on Pins 34 and 35.

The RGB signal from the Scaler is fed to the TV Display Processor, 7221. RGB is output from this IC to the CRT panel. Horizontal and Vertical drive is output to the Family board.
TV Display Processor
IC 7221 is used in a large number of Philips chassis for a long period of time. RGB in inserted in Pins 30, 31, and 32. This signals are converted to a YUV format before being fed to the Color level control. RGB from 7206 is inserted on Pins 35, 36, 37, and 38. The signal then goes to a Brightness and Controls control circuit. RGB to the CRT panel is output on Pins 40, 41, and 42. During warm up, a cathode calibration signal is fed to the CRT panel on the RGB lines. This signal is then fed back to CRT panel.

RGB is fed to the CRT panel on connector 1331. The CRT panel for the L05HD has a single chip CRT drive circuit. RGB is fed to 7330 on Pins 1, 2, and 3. Signal is output to the CRT on Pins 7, 8, and 9. BC_INFO or Cutoff on Pin 5 is fed back to the TV Signal Processor on the Trident panel. The IC is powered by a 200 volt supply on Pin 6.
DC operating voltages for the CRT panel are located on connector 1351. The Filament voltage is located on Pin 2. The 200VA voltage on Pin 5 powers 7330. The VBAT voltage on Pin 3 and the +12V_LOT voltage on Pin 6 powers the SVM circuit.

SVM

There are two coils on the deflection coil in addition to the Vertical and Horizontal winding.  The SCAVEM coil (Scan Velocity Modulation) sharpens the edges between light and dark transitions.
The SVM_ROT signal drives both the SCAVEM and the Rotation coil. The SCAVEM circuit is powered by the Vbatt and +12V_LOT supplies. Capacitor 2376 blocks the dc Rotation signal to prevent it from entering the SCAVEM circuit. Capacitor 2381 blocks the higher frequency SCAVEM signal to prevent it from affecting the Rotation drive.

SVM coil and rotation circuit

Audio

All audio processing and control is performed by the Hercules IC 7200 located on the main board.
Audio is included in the HDMI bit-stream. Digital audio from 7002 is fed to IC 7011, Audio DAC. Audio from 7011 is fed to IC 7050, switch, which has only one input since the second input is not used in the HD version. The output of 7050 is fed to the Hercules IC located on the Main board. Audio for the CVI input should be inserted into AV1. Audio is output from the Hercules on Pins 68 and 69 to the Audio Amplifier, IC 7990. This is a two channel 20 watt amplifier.

Audio output
Main audio is output on Pins 68 and 69 and fed to the audio amplifier 7990. The audio amplifier is a dual 10 watt amplifier. It is powered by the +VAUDIO and -VAUDIO supplies. These are +16 and -16 volts. To mute the amplifier, the VOL_MUTE line goes Low switching transistor 7992 Off switching transistor 7991 On. The output of the amplifier is fed to the Side Jack panel.
Monitor audio is output on Pins 66 and 67 of 7200. These outputs are muted by the STBY_CONT and POWER DOWN lines. The POWER DOWN line is High during normal operation. As the set powers off, this line goes Low, switching 7993 Off. Transistor 7104 then switches On to mute the output. The STBY_CONT line goes High when the set is turned Off turning 7994 On, muting the output. Capacitor 2999 delays the turn-on of 7993 to prevent a pop in the speaker at set turn ON.

How to enter the adjustment mode Philips L05HD NTSC TV – Power supply schematic

Philips L05HD – CRT TV – Power supply section circuit diagram and working principles.

The L05HD TV chassis is designed for the model year 2005. This set is High Definition ready with an NTSC tuning system. To receive the ATSC channels a set top box is required.

Press the Menu button to make a selection. Press the Cursor up-down buttons on the remote to highlight the desired selection. Press the right Cursor button to make the selection.

  The NTSC tuning system features 181 channels with on-screen display. The main tuning system uses a tuner, a microcomputer, and a memory IC mounted on the main panel. The microcomputer communicates with the memory IC, Remote Receiver, Tuner, Signal processing IC, and HD processing section. The Memory IC retains the settings for favorite stations, customer-preferred settings, and circuit settings. The circuit settings can be accessed by the service technician via the Service Alignment mode.

The On-screen graphics and Closed Caption decoding are done within IC 7206 located on the HD panel. They are added to the main signal in the Display Processor, 7221, located on the HD panel.

Press the Menu button on the remote and press the Cursor up-down button to obtain the screens.

Setting up the access code.

1. Press the Menu button on the remote to display the on-screen menu.
2. Press the Cursor up or down buttons until the word features are highlighted.
3. Press the Cursor right button to display the features menu options.
4. Press the Cursor up or down buttons until the words auto lock is highlighted.
5. Press the Cursor right button. The screen will read, “Access Code ----”
6. Using the number buttons, enter 0, 7, 1, 1. [XXXX will appear as you press the buttons.]
Incorrect code will appear on the screen. Enter 0711 again.
7. The screen will ask you to enter a new code. Enter any 4 digit code.

Main SM Power Supply Block

  The Power supplies are both located on the Family board. The supplies are divided into two sections, the Auxiliary and Main section. A single filter and rectifier circuit supplies both sections. The Auxiliary supply operates in a low power mode when the load is reduced. In the standby mode, the 3.3 and 6 volt supplies are operating. The 3.3 volt supply provides power to the processor section of the Hercules. The 6 volt supply provides power to the IR receiver. The Main supply is switched Off via the Standby line.

  When the set is turned On, the "B" line from the Hercules processor goes High switching 7547 which turns 7535, 7509, and 7545 On. The +3V3A, +6VA, +12VA, and +8VA supplies are then switched On. The load placed on the Aux Power supply will cause it to switch to the full power mode. At the same time, the STBY line switches Low turning the Main SMPS supply On. The supply produces a +6 volt, +140 volt, -16 volt, and +16 volt supplies.
The +Vaudio (+16 volt) supply switches on the degauss relay.

Main SMPS schematic

Auxiliary Power Supply

  IC 7510 is the heart of the Auxiliary Power supply. In the Standby mode, VIA the current sensing and Control circuits, a low power condition is detected by the IC. The IC then goes into a Burst Mode operation to reduce the power used by the circuit. In the Burst Mode, the supply will operate at approximately 25 kHz. In full power operation the frequency will be approximately 66 kHz.

  When power is first applied to the set, Start up is supplied to the IC by the internal Start-Up current through Pin 14. Startup voltage is also applied to the IC to Pin 2 by the AC_IN line which is tied to the neutral side of the AC line. During normal operation, power is supplied to the IC by the HOT windings, Pins 1 and 2, of transformer 5504. Output drive from Pin 11 is applied to the Gate of Transistor 7525. Voltage developed across the current sensing resistors in the Source of 7525 provides current sense information to the IC. When 7525 is switched Off, the voltage on Pin 1 of 5504 goes High. This winding supplies the operating voltage the power supply circuit. It also turns Transistor 7567 On causing the Gate of 7525 to stay Low as long as Pin 1 of 5504 is High. This prevents 7525 from turning On until the field of 5504 has collapsed.

Auxiliary Power Supply Schematic

  Regulation is accomplished by monitoring the +3 volt supply. This voltage is fed to Shunt regulator 7542 which controls the current through opto-isolator 7516. Shunt Regulator 7542 begins conducting when Pin 3 of the IC reaches 2.5 volts. At this point current flows through the opto-isolator, 7516. The transistor inside 7516 turns On applying a control voltage to Pin 6 of 7510. If a problem should develop in the feedback circuit causing an excessive voltage on Pin 6, Transistor 7549-2 will turn On, switching Transistor 7532 On. This will a voltage to the Demag circuit on Pin 7 causing the IC to latch Off. The IC will stay latched until power is removed and reapplied to the set.

  In the Standby mode, the "B" control line from the Hercules Processor is Low. Only the +3, +3V3, and +6 volt supplies are present. When the set is turned On, the "B" line will go High, turning Transistors 7509, 7545, and 7535 On. This will switch On the +8VA, +12VA, +8V, +3V3A, +6VA, and +5V supplies.
  In normal operation, voltage from Pin 12 of 5504 is rectified by 6540 to produce a negative voltage which prevents Transistor 7561 from turning On. If AC is removed from the set, this negative voltage will disappear. The voltage across the filter capacitors on the +3V line will turn 7561 On. The Power Down line will then go Low signaling the processor to shut the set down.

  The Main Power supply provides the VBAT (141 volt), and Audio voltage supplies. This supply is switched Off during the Standby mode. During Standby the STBY_Con line is High which turns Transistor 7573 On. This causes the opto-isolator 7513 to turn On hard. This places a higher voltage on the control Pin of IC 7511 causing the IC to shut down. The operating voltage from the Auxiliary supply keeps a small voltage on Pin 2 of 7511 to prevent it from cycling On and Off. Output from Pin 11 of 7511 drives FET 7512 which drives Transformer 5512. When Pin 2 of 5512 goes High, Transistor 7514 is switched On turning 7512 Off. This is to prevent 5512 from becoming saturated.

  When the set is turned On, the STBY_Con line goes Low switching 7573 Off. The VBAT supply is the reference voltage for regulation. Since this voltage is missing during startup, the Shunt Regulator 7571 is turned Off. The voltage on Pin 6 of 7511 goes Low, which turns the drive from the IC On. When the set is On during normal operation, the supply voltage on Pin 2 of the IC is supplied by Pin 2 of Transformer 5512. When the VBAT supply reaches the correct voltage, Pin 3 of the Shunt Regulator 7571 reaches 2.5 volts switching it On. This switches the opto-isolator On to provide a regulation feedback path.

  Transistor 6551 provides a power on ramping of the VBAT supply.

Service Alignment Mode SAM
Making changes in the settings requires entering the SAM. To enter SAM, press [0 6 2 5 9 6

Info] on the remote control. Use the cursor-up and cursor-down buttons to highlight a selection. Press the cursor-right, cursor-left buttons, or enter a value to make changes. 

Color TV schematic Using TDA9570 – Syscon Chroma Jungle IC (My service table today)

Used ICs: TEA1533AT (SMPS controller), TF6NK90Z (SMPS switching FET), PT11400 (Remote control IC), TDA9570 (Syscon Chroma Jungle), TDA1517 (Audio output IC), LA78040 (Vertical scan output IC), BU1508DX (Horizontal scan output transistor)

This circuit have been used with many brand CTVs.  The main fault found with this circuit is the breakage of the Horizontal scan output transistor (BU15508DX).  If this transistor is found leak (Collector to Emitter), be sure to measure the frequency at pin number (30 – HOUT) of IC TDA9570H.  {If the set does not turn ON, and the main fuse on board is OK, is the symptom  of horizontal output trannsitor damage. The power LED at the front panel of the  set will flash once, and will immediately go  off - (Short circuit protection).In this case, just de-solder out the horizontal output transistor, and switch ON the set without it. The power light should turn  ON and remain lit; provided there is no fault with it's circuit.  You can measure all the SMS out  voltages now} In most cases this frequency will vary much higher than normal.  If you found this frequency to be very high (it can be measured without inserting a new horizontal transistor in place), make sure it to be under limited frequency; usually between (15500 to 17800 Hz), before replacing the horizontal output transistor, otherwise the transistor will get damaged again, as soon as you switch ON the set, not giving any chance to you checkout the fault. Check and make sure the freewheeling capacitor, that connected in between the collector of the horizontal output transistor to Ground is good. Make sure the solder terminals of this capacitor have no loose solder at all. If this capacitor (usually a 0015 to 0047MFD-2500VDC.) is not good or having a loose solder terminal, the transistor will get damaged.

  More to say, if the deflection yoke (Horizontal scan side winding) have an internal short in between its windings, this transistor will overheat in no time, and will fail.  So after replacing this transistor, check the heat of the transistor, periodically at about 2 minute’s interval.  It might get warm, but not too hot.  Feel this heat at its heat-sink.

Click on the schematic to magnify

  Another possibility is with DC output voltage from the SMPS converter.  If this voltage go beyond normal [High], the transistor will get damaged.  If you found this voltage to be abnormal, check and clear all the faults with the SMPS circuit first.

  The components used in the SMPS of this circuit are cheap and easily available at the local electronic spare part market. When work with it, just replace all the main components; (SMPS switching transistor, the opto-coupler and the control IC (TEA1533), all at the same time.

Akira CT-25XG9-CHASSIS: 5N11(CT-25XG9A, CT-25XG9AN) How to enter the factory mode, adjustments, full schematic, Option codes

Akira 25 inch color TV. Used ICs: STR6656, SE140, AN5891K, TA8256 or TA8246, MSP3410D, MN5198 or MN5199, CD4052, TA8427, 2SC5150(Horizontal Output Transistor), STV5348, 24C04A(Memory)

EEPROM partial initializing

Go to the function set menu (there are two methods: (a / b)

a) Press 'VOL+' key and 'VOL-' key on the control board at the same time and switch on power switch, then go to the function set menu.
After TV is ON; press "factory" key twin then go to the function set menu.

b) Press 'PM' key and 'SM' key on the control board at the same time until the “INITIAL PART OK” appears.

This means the memory having been partially initialized. 

Operate repeatedly if the picture has no change.

All of the TV set EEPROM must be partially initialized before ex-factory or after change of the Chroma IC NN5198 / NN5199 or fully EEPROM initialized after change of the EEPROM 24C04 (OR 24C08,24C16)

Do a search and store.

CHASSIS ADJUSTMENT

PAL system vertical pincushion adjustment.

Receive PAL system cross hatch pattern signal.

Press 'factory' key one time, go to system parameter adjustment menu.

Press 'MENU' key, go to horizontal and vertical parameter adjustment menu.

Select 'V LINE' and 'V SCURVE' by pressing 'PROG+' key and 'PROG-' key.

press 'VOL+' key and 'VOL-' key and adjust corresponding parameter to obtain picture's vertical pin cushion a good status PAL system.

White Balance adjustment: For Factory Auto Computer adjustment

a. Receive white balance test signal.

b. Set picture "MILD" mode.
c. Insert the special plug into CN002, press adjustment key which belongs to white
balance adjustment equipment and go to auto white balance adjustment.
d. After adjustment well, remove the plug.
For Factory Auto Computer adjustment
a. Press 'factory' key one time and go to system parameter adjustment menu.
b. Press "MENU" key once, then go to the White Balance adjustment menu.
c. Press ‘Prog +' key and 'Prog -' key to select the R, G, B cutoff and R, B Driver.
d. Press 'VOL+' key and 'VOL-' key to change. Or using the below direct key
e. Key: 0 for SUB-BRIGHT, 1 for CUTOFF-R, 2 for CUTOFF-G.
3 for CUTOFF-B, 4 for DRIVER-R, 5 for DRIVER-B
f. Recall for toggle the Sub-Bright adjustment (Min. contrast, some CPU version do not work)

Warm up mode

a. Switch on power switch and Press 'factory' key one time.

Switch off power switch and switch on power again.

 At this time there is no signal white raster and TV won't switch off automatically. TV receiver can be sent to warm up line.
b. Before exit warm up line, press 'factory' key three times to continue, at this time exit warm up mode, there is no signal and the LOGO ‘AKIRA’ pattern will appear.
NOTES

Connect the remote IC PIN7 and PIN16 through a jiggle switch on the USER remote handset. 

This switch is defined as "screen" key.

 Connect the remote IC PIN8 and PIN16 through a jiggle switch on the USER remote handset. 

This switch is defined as "factory" key.

On the product line's alignment service we must use special memorizer that has been well written with respective correct version data.

If having no special memorizer that has been well written with data when servicing out of factory, we can use blank new EEPROM. Then the new EEPROM will be automatically initialized with default data after main power switch is on. Most parameters are free-alignment after initialized; only need adjust the several parameters of function set parameter and system parameter adjustment menu.

If no blank new EEPROM or no special memorizer that has been well written with data, we can use memorizer that has been written with old data instead, but must be totally reinitialized; the operation is as following

a) After TV is on, press "factory" key twin, ­then go to the function set menu.
b) Press 'AV/TV' key and 'P.M' key on the control board. 

The TV turns off automatically. This means the memory having been totally initialize. 

Operate repeatedly if the picture has no change.
c) Switch off and exit.
d) After initialized, adjust the several parameters of function set parameter and system parameter adjustment menu.

The parameters of function set parameter and system parameter adjustment menu mustn't be adjusted.

Ensure no adjustment on the following parameter except those parameter mentioned here.

System parameter adjustment menu (This is coming from the NN5198/ NN5199)
AFT
VIF VCO
H VCO
VIFDET NEG
VIFDET INT
VIFDET EXT

The ninth digital and the tenth digital of function set parameter.
These parameters must be IC interior values. 

If the above parameters have been changed, we must partially initialize the EEPROM.

Two different initializing
a) Fully initialize: 

Initialize the EEPROM's most work data and preset default value. Including: work parameter of NN5199, horizontal and vertical parameter, OPTION parameter (via. function set parameter), picture mode parameter, volume mode parameter and white balance parameter.
b) Partially initialize: 

Only initialize work parameter of NN5199 and the ninth digital and the tenth digital of function set parameter(via. ISUD0, ISUD1,ISUD3,ISUD4,ISUD5),preset as interior values.

If use 25 inch or above Pure Flat tube, adjustment of horizontal size and pincushion distortion must be done as follows.

a) Receive 60dBuV PAL system monoscope pattern.
b) Press 'factory' key one time and go to system parameter adjustment menu.
c) Press 'MENU' key and select ' Position Menu ' as below:

Vertical position – 00 to 07

Horizontal position – 00 to 1F

V EHT(vertical shape) – 00 to 0F

H EHT (horizontal shape) – 00 to 0F

Press 'MENU' key and select ' geometry Menu'

Adjust the needy parameters.

Exit system parameter adjustment menu by pressing 'factory' key twin.

Option Codes

Press the 'factory' key twin and go to Option Code Menu

The first digit 8 Digit is set by Factory. The last two digit “9” and “A” is the random data from NN5198/NN5199

Schematic [Click on the pictures to zoom in)