Philips 26LL590121- CRT TV, Service mode and adjustments, convergence adjustments, How to test an opto-isolator, How to check a programmable regulator IC and more....
Common to all models of Philips large screen CRT TV sets 0n F8 Chassis
POWER SUPPLY DESCRIPTIONThe F8 chassis family uses a free-running switch-mode power supply with a single controller IC. As AC power is applied to the set, approximately 160volts DC is developed by the bridge rectifiers and fed to the primary winding of the power transformer, then to the FET switch. The start voltage for the power supply is taken from the hot leg of the AC input. This voltage goes to controller IC 7520. A separate operating voltage is developed from the power transformer, rectified, and applied to IC 7520. The power supply is on all the time; there is no standby mode. The set is turned on and off by the microprocessor switching the +8 volt regulator on and off. The +8 volt is the supply voltage for the signal processor.
IC7520 is regulated by means of a feedback circuit, monitoring the +11 volt secondary line. Any voltage variations are reflected back to the controller IC 7520 through an Opto-Coupler IC and change the operating frequency of the power supply as needed. REMEMBER TO USE AN ISOLATION TRANSFORMER WHEN SERVICING THIS CHASSIS.
Complete Circuit Description
When AC is applied, current flow through the Bridge Rectifier circuit causes two simultaneous events to occur:
1. Capacitor 2508 begins to charge to 160 volts DC.
2. Capacitor 2540 begins to charge to 14.5 volts DC.
When capacitor 2508 is fully charged, 160 volts is applied to the drain of 7518, through transformer 5545. When capacitor 2540 is fully charged, 14.5 volts is applied to pin 1 of 7520. This voltage will cause 7520 to begin oscillating and putting out a pulse train on pin 3. These pulses will cause 7518 to conduct which will cause a field to build up in the primary winding of transformer 5545. When this field collapses, a field will be induced in the secondary windings. Pins 8 and 9 of 5545 will output to diode 6540, which will rectify the pulses. Capacitor 2540 will filter the pulses and provide approximately 12.5 volts to pin 1 of 7520. This now becomes the RUN voltage for 7520.
Feedback control is accomplished by monitoring the 140 volt line. The 140 volt, +VBATT supply is sent through resistor 3571 to pin 3 of the Programmable Regulator IC, 7570. This regulator will turn on at 2.5 volts DC. Current will then begin to flow through the diode portion of the Opto-Isolator IC, 7581. The intensity of light caused by this current flow will then control the conduction of the transistor portion of 7581. The voltage appearing on pin 4 of 7581 is then monitored by pin 14 of 7520 where it is compared to a 2.5 volt reference voltage. Changes felt on pin 14 will control the width of the pulses coming out of pin 3. These pulse changes will determine the “on” time of 7518
F8 CHASSIS INTRODUCTION
The F8 chassis is a leader TV chassis produced by Philips Consumer Electronics Company for the 1999 model year. The F8 chassis is used in sets with 25“ and 27“ screen sizes. The F8 chassis is a global design and is oriented front to rear, or ”north to south“, as it has been called. The F8 chassis tuning system features 181 channels with on-screen display (OSD). The main tuning system uses a tuner, a microcomputer IC, and a memory IC mounted on the main chassis. The microcomputer communicates with the memory IC, the customer keyboard, remote receiver, U/V tuner, signal processor IC and the audio output IC via the I2C bus. The memory IC retains the settings for favorite stations, customer-preferred settings, and service/factory data.
The F8 chassis uses a Very Large Scale (VLSI) Integrated Circuit for signal processing. This IC performs video IF, sound IF processing, AGC control, horizontal and vertical drive and synchronization, also luminance/chrominance processing. The on-screen graphics and closed caption decoding are done within the microprocessor, and then sent to the signal processor IC to be added to the main signal.
The F8 chassis utilizes a switch mode power supply for the main voltage source. The chassis has a hot chassis ground reference on the primary side of the power supply, and a cold ground reference on the secondary side of the power supply and the rest of the chassis. ALWAYS USE AN ISOLATION TRANSFORMER WHEN SERVICING THIS CHASSIS FOR YOUR SAFETY.
Vertical Circuit
The vertical drive signals are internally generated in IC7250 and are output on pins 46 and 47. From there they are sent to the Vertical Output IC, 7401, pins 1 and 7.
Inside the IC, the waveforms are amplified, shaped and output on pins 5 and 6. The output on pin 5 is the waveform that drives the yoke and provides feedback to the IC.
The output on pin 6 is the Vertical Synchronization pulse that is sent to pin 37 of the microprocessor.
Horizontal Circuit
The horizontal drive pulse is internally generated in IC7250 and is output on pin 40.
This pulse is amplified by transistor 7461 and transformer coupled by 5461 to the base of the Horizontal Output, 7460, where it is amplified.
Shaping takes place in the collector circuit (C2463 and C2465), which results in a perfectly timed 825 volt peak-to-peak pulse to drive the deflection yoke and the flyback transformer.
The Flyback Transformer secondary windings produce 10 working voltages:
VlotAux-11V, VlotAux+11V and VlotAux+50V all supply power to the vertical output IC, 7401.
The 187 volt VideoSupply, the filament voltage, Screen voltage (VG2) and Focus voltage all go to the CRT board.
The EHT voltage goes to the anode connection on the CRT.
The VT_Supply and the VlotAux+5V Supply both go to the Tuner. The VT_Supply is zenered down to 33 volts for tuning voltage and the VlotAux+5V supply acts as B+ for the Tuner and also becomes the +5 volt supply. The VlotAux+5V supply also provides voltage to the Audio Circuits.
Shutdown Circuits
Three of the shutdown protection circuits are derived from pins 7 and 10 of the Flyback Transformer.
If the voltage on the filament line (pin 7) goes too low, transistor 7482 will turn on and apply a positive voltage to the P9StbyOn+Protn line.
If the voltage on the filament line (pin 7) goes too high, transistor 7462 will turn on causing transistor 7463 to turn on and apply a positive voltage to the HEW_Protn line.
If the beam current (pin 10) becomes excessive, the voltage on the EHT line will go toward the negative direction. This action will cause transistor 7481 to turn on and place a positive voltage on the P9StbyOn+Protn line.
For sets having East West correction circuitry, pin 10 of 5545 is being monitored by transistor 7470. Transistors 7470, 7481 and 7482 all control transistor 7605. In the event of a problem, 7605 will bring pin 16 of the Microprocessor, 7600 low, shutting the set down.
How to Check an Opto-Isolator
Procedure
Using a basic diagram taken from the F8 schematic, we are going to determine whether or not IC7581 is functioning properly.
Step -1
Apply the positive lead of a variable DC power supply to the positive terminal of capacitor 2561. Connect the negative lead of the power supply to pin 1 of IC7570. By connecting them this way we are able to use resistors 3685 and 3575 as protection for IC7570.
Step -2
Apply the positive lead of an ohm meter to pin 5 and the negative lead to pin 4 of 7581. Set the ohmmeter to the 2K scale or greater.
Step -3
Slowly increase the DC voltage from 0 to 5 volts. If the IC is good, you will see the reading on the ohmmeter start decreasing as the voltage approaches 5 volts.
CAUTION: Do not exceed 5 volts DC.
How to Check a Programmable Regulator IC
Procedure
Using a basic diagram taken from the F8 schematic, we are going to determine whether or not IC7570 is functioning properly.
Step -1
Apply the positive lead of a variable DC power supply to pin 3 of IC7570 and the negative lead to cold (chassis) ground.
Step -2
Apply the positive lead of your DVM to pin 1 of IC7570 and the negative lead to cold ground.
Step #3-
Slowly increase the DC voltage from 0 to 2.5 volts. If the IC is good,
you will begin to see a DC voltage reading on your DVM as soon as the
applied DC voltage is 2.5 volts.
Service Alignment Mode (SAM)
1. The Service Alignment Mode (SAM) is used to make tuning adjustments,
align the white tone, adjust the picture geometry, and make sound
adjustments.
2. To enter the Service Alignment Mode (SAM), press the following key
sequence on the remote control transmitter: 0-6-2-5-9-6-Status
Do not allow the display to time out between entries while keying the sequence.
SAM can also be entered by pressing the Channel Down and Volume Down
keys on the local keyboard simultaneously while in SDM mode.
When Service Alignment Mode is entered, the text "SAM" will be displayed in the top right corner of the screen.
3. When Service Alignment Mode is entered, service unfriendly modes are disabled.
The following volatile SAM item values are set:
AKB = 0
VSD = 0
AFW = 275 kHz
SBL = 0
4. When the unit is operating in Service Alignment Mode, all normal
on-screen displays are suppressed and replaced by a special service
display. The first screen seen upon entering SAM is the ”top level SAM
menu.“ The service technician must return to the top level SAM menu
before exiting with a power-off command.
A sample SAM top level menu display is shown below.
Explanation of top level SAM menu display:
The Software Identification, Cluster, and Version are explained in the
Service Default Mode section under ”Explanation of Display.“
The Menu Items and Sub Menus are explained below.
Note: The ”Audio“ sub menu will not be seen on screen when Service
Alignment Mode is first entered. Use the Menu Up and Menu Down buttons
on the remote control to view all menu items and sub menu choices.
5. To select a menu item or a sub menu in SAM, use the Menu Up or Menu
Down keys on the remote control to highlight the item or menu you wish
to adjust.
6. To change the value of a highlighted SAM menu item (AKB or VSD), use the Menu Left or Menu Right keys on the remote control.
7. To enter a highlighted SAM sub menu, use the Menu Left or Menu Right
keys. After entering the sub menu, use the Menu Up or Menu Down to
select an item within the sub menu.
Use the Menu Left or Menu Right keys to change the value of the selected
item. Press the Menu button to return to the top level SAM menu.
8. Press the Menu button on the remote control while in SAM to switch
the software to a Virtual Customer Mode; the text "SAM" will still be
displayed in the upper right corner of the screen. In this mode, all
customer menu adjustments to the set can be made. From the Virtual
Customer Mode, press the Menu button to return to the SAM Menu.
9. Press the Status button on the remote control to toggle the OSD (except ”SAM“) ON and OFF.
10. To exit the Service Alignment Mode, turn the set off with the Power
button on the remote control. To turn off the set without exiting SAM
(or erasing any stored error codes), unplug the AC cord. When the set is
powered on again, the Service Alignment Mode will still be active.
Note: When SAM is exited or a power interrupt occurs, the volatile SAM
items AKB, VSD, AFW, and SBL will be reset to their original values.
Main Menu
The SAM main menu contains the following items:
AKB
VSD
Tuner sub menu
White Tone sub menu
Geometry sub menu
Audio sub menu
Tuner sub menu
The tuner sub menu contains the following items:
IF-PLL
AFW
AGC
YD
CL
AFA and AFB
The items AFA and AFB cannot be selected; they are for monitoring purposes only.
The item values are stored in EEPROM if this sub menu is left.
Tuner Adjustment:
AGC Takeover Point (AGC):
1. Enter the Service Alignment Mode (SAM) by pressing the following key sequence on the remote control transmitter: 0-6-2-5-9-6-Status
Do not allow the display to time out between entries while keying the sequence.
2. From the top level SAM menu, use the Menu Up/Down keys to highlight the Tuner sub menu.
3. Use the menu left/right keys to enter the Tuner sub menu.
4. In the Tuner sub menu, use the Menu Up/Down keys to highlight AGC.
5. Use the Menu Right key to raise the value of AGC until snow appears in the picture.
6. Then use the Menu Left/Right keys to reduce AGC value until the snow disappears.
a. AGC values between 10 and 20 are nominal.
b. Single digit AGC values may cause overload.
7. Upon completion of Tuner adjustment, press the Menu button to return to the top level SAM menu
AGC Takeover Point (AGC):
1. Enter the Service Alignment Mode (SAM) by pressing the following key sequence on the remote control transmitter: 0-6-2-5-9-6-Status
Do not allow the display to time out between entries while keying the sequence.
2. From the top level SAM menu, use the Menu Up/Down keys to highlight the Tuner sub menu.
3. Use the menu left/right keys to enter the Tuner sub menu.
4. In the Tuner sub menu, use the Menu Up/Down keys to highlight AGC.
5. Use the Menu Right key to raise the value of AGC until snow appears in the picture.
6. Then use the Menu Left/Right keys to reduce AGC value until the snow disappears.
a. AGC values between 10 and 20 are nominal.
b. Single digit AGC values may cause overload.
7. Upon completion of Tuner adjustment, press the Menu button to return to the top level SAM menu
White Tone sub menu
The white tone sub menu contains the following items:
Normal Red
Normal Green
Normal Blue
Delta Cool Red
Delta Cool Green
Delta Cool Blue
Delta Warm Red
Delta Warm Green
Delta Warm Blue
Note: Delta values are only used in models with the item ”Color Temperature“ in the customer menu.
OSD is kept to a minimum in this menu, in order to make white tone alignment possible.
The item values are stored in EEPROM if this sub menu is left.
The Contrast Plus feature (black stretch) is set to OFF when the White Tone sub menu is entered.
The white tone sub menu contains the following items:
Normal Red
Normal Green
Normal Blue
Delta Cool Red
Delta Cool Green
Delta Cool Blue
Delta Warm Red
Delta Warm Green
Delta Warm Blue
Note: Delta values are only used in models with the item ”Color Temperature“ in the customer menu.
OSD is kept to a minimum in this menu, in order to make white tone alignment possible.
The item values are stored in EEPROM if this sub menu is left.
The Contrast Plus feature (black stretch) is set to OFF when the White Tone sub menu is entered.
White Tone Adjustments:
Note: The following procedure was performed with a Sencore VG91 Universal Video Generator providing grey scale bars.
1. Enter the Service Alignment Mode (SAM) by pressing the following key sequence
on the remote control transmitter: 0-6-2-5-9-6-Status.[Do not allow the display to time out between entries while keying the sequence.]
2. From the top level SAM menu, use the Menu Up/Down keys to highlight the White Tone sub menu.
3. Use the Menu Left/Right keys to enter the White Tone sub menu.
4. Set the VG91 Generator as follows: STD TV Ch. 3, RF-IF Range set to HI, RF-IF Level set to NORMAL (1), Video Pattern = Raster, R-G-B raster controls OFF.
5. Connect the RF output of the generator to the Television Antenna Input, and adjust the VG91 level to remove any snow from the raster.
6. Turn off chroma at generator and leave grey scale bars.
7. From the White Tone sub-menu, use the Menu Up/Down keys to select Normal Red, Normal Green, or Normal Blue. Then use the Menu Left/Right keys to adjust the values to obtain the best white balance.
8. A reasonable starting point for NORMAL is:
Normal Red=45, Normal Green=32, Normal Blue=39
9. After NORMAL is set, use the same method to set DELTA COOL and DELTA WARM as offsets.
A reasonable starting point for DELTA COOL is:
Delta Cool Red=(–2), Delta Cool Green=0, Delta Cool Blue=+6
A reasonable starting point for DELTA WARM is:
Delta Warm Red=+2, Delta Warm Green=0, Delta Warm Blue=(-7)
10. After the values are set, or if no changes are required, press Menu to return to the top level SAM menu.
Note: The following procedure was performed with a Sencore VG91 Universal Video Generator providing grey scale bars.
1. Enter the Service Alignment Mode (SAM) by pressing the following key sequence
on the remote control transmitter: 0-6-2-5-9-6-Status.[Do not allow the display to time out between entries while keying the sequence.]
2. From the top level SAM menu, use the Menu Up/Down keys to highlight the White Tone sub menu.
3. Use the Menu Left/Right keys to enter the White Tone sub menu.
4. Set the VG91 Generator as follows: STD TV Ch. 3, RF-IF Range set to HI, RF-IF Level set to NORMAL (1), Video Pattern = Raster, R-G-B raster controls OFF.
5. Connect the RF output of the generator to the Television Antenna Input, and adjust the VG91 level to remove any snow from the raster.
6. Turn off chroma at generator and leave grey scale bars.
7. From the White Tone sub-menu, use the Menu Up/Down keys to select Normal Red, Normal Green, or Normal Blue. Then use the Menu Left/Right keys to adjust the values to obtain the best white balance.
8. A reasonable starting point for NORMAL is:
Normal Red=45, Normal Green=32, Normal Blue=39
9. After NORMAL is set, use the same method to set DELTA COOL and DELTA WARM as offsets.
A reasonable starting point for DELTA COOL is:
Delta Cool Red=(–2), Delta Cool Green=0, Delta Cool Blue=+6
A reasonable starting point for DELTA WARM is:
Delta Warm Red=+2, Delta Warm Green=0, Delta Warm Blue=(-7)
10. After the values are set, or if no changes are required, press Menu to return to the top level SAM menu.
Geometry sub menu
OSD is kept to a minimum in this sub menu in order to make picture geometry adjustments possible.
The item values are stored in EEPROM if this sub menu is left.
The value of item Service Blanking (SBL) is not stored in EEPROM, and it is set to OFF when the geometry sub menu is exited
OSD is kept to a minimum in this sub menu in order to make picture geometry adjustments possible.
The item values are stored in EEPROM if this sub menu is left.
The value of item Service Blanking (SBL) is not stored in EEPROM, and it is set to OFF when the geometry sub menu is exited
Geometry Adjustments:
Notes:
1. The following Geometry adjustments were performed with a Sencore VG91Universal Video Generator.
2. Set the VG91 Generator as follows: STD TV Ch. 3, RF-IF Range set to HI, RF-IF Level set to NORMAL (1), Video Pattern = Raster, R-G-B raster controls OFF,
crosshatch or center cross pattern as required.
3. Connect the RF output of the generator to the Television Antenna Input, and adjust the VG91 level to remove any snow from the raster.
Vertical Shift (VSH):
Notes:
1. The following Geometry adjustments were performed with a Sencore VG91Universal Video Generator.
2. Set the VG91 Generator as follows: STD TV Ch. 3, RF-IF Range set to HI, RF-IF Level set to NORMAL (1), Video Pattern = Raster, R-G-B raster controls OFF,
crosshatch or center cross pattern as required.
3. Connect the RF output of the generator to the Television Antenna Input, and adjust the VG91 level to remove any snow from the raster.
Vertical Shift (VSH):
1. Enter the Service Alignment Mode
(SAM) by pressing the following key sequence on the remote control transmitter:
0-6-2-5-9-6-Status
Do not allow the display to time out between entries while keying the sequence.
2. From the top level SAM menu, use the Menu Up/Down keys to highlight the Geometry sub menu.
3. Use the Menu Left/Right keys to enter the Geometry sub menu.
4. In the Geometry sub-menu, use the Menu Up/Down keys to select VAM.
5. Input a center cross pattern to the antenna/cable input terminal.
6. Using the Menu Left/Right keys, adjust VSH so that the horizontal bar is properly centered, top to bottom.
7. If other Geometry adjustments are needed, proceed to the necessary adjustment using the Menu Up/Down buttons.
8. Upon completion of Geometry adjustments, press the Menu button to return to the top level SAM menu.
Do not allow the display to time out between entries while keying the sequence.
2. From the top level SAM menu, use the Menu Up/Down keys to highlight the Geometry sub menu.
3. Use the Menu Left/Right keys to enter the Geometry sub menu.
4. In the Geometry sub-menu, use the Menu Up/Down keys to select VAM.
5. Input a center cross pattern to the antenna/cable input terminal.
6. Using the Menu Left/Right keys, adjust VSH so that the horizontal bar is properly centered, top to bottom.
7. If other Geometry adjustments are needed, proceed to the necessary adjustment using the Menu Up/Down buttons.
8. Upon completion of Geometry adjustments, press the Menu button to return to the top level SAM menu.
Vertical Amplitude (VAM):
1. Enter the Service Alignment Mode (SAM) by pressing the following key
sequence on the remote control transmitter: 0-6-2-5-9-6-Status
Do not allow the display to time out between entries while keying the sequence.
2. From the top level SAM menu, use the Menu Up/Down keys to highlight the Geometry sub menu.
3. Use the Menu Left/Right keys to enter the Geometry sub menu.
4. In the Geometry sub-menu, use the Menu Up/Down keys to select VAM.
5. Input a crosshatch pattern to the antenna/cable input terminal.
6. Using the Menu Left button, reduce the value so that the picture does not fill the entire screen.
7. Use the Menu Up/Down keys to select VSH (Vertical Shift) from the
Geometry sub-menu and, using the Menu Left/Right keys, center the
picture on the screen, top to bottom.
8. Using the cursor up/down keys, select VAM from the Geometry sub-menu,
and use the Menu Right key to increase the value to obtain a slight
over scan.
9. If other Geometry adjustments are needed, proceed to the necessary adjustment using the Menu Up/Down buttons.
10. Upon completion of Geometry adjustments, press the Menu button to return to the top level SAM menu.
Horizontal Shift (HSH):
Note: This adjustment centers the video on the raster. It does not move the raster.
1. Enter the Service Alignment Mode (SAM) by pressing the following key
sequence on the remote control transmitter: 0-6-2-5-9-6-Status
Do not allow the display to time out between entries while keying the sequence.
2. From the top level SAM menu, use the Menu Up/Down keys to highlight the Geometry sub menu.
3. Use the Menu Left/Right keys to enter the Geometry sub menu.
4. In the Geometry sub-menu, use the Menu Up/Down keys to select HSH.
5. Input a center cross pattern to the antenna/cable input terminal.
6. Using the Menu Left/Right keys, adjust HSH so that the vertical bar is properly centered, left to right.
7. If other Geometry adjustments are needed, proceed to the necessary adjustment using the Menu Up/Down keys.
8. Upon completion of Geometry adjustments, press the Menu button to return to the top level SAM menu.
Vertical Slope (VSL):
1. Enter the Service Alignment Mode (SAM) by pressing the following key sequence on the remote control transmitter: 0-6-2-5-9-6-Status
Do not allow the display to time out between entries while keying the sequence.
2. From the top level SAM menu, use the Menu Up/Down keys to highlight the Geometry sub menu.
3. Use the Menu Left/Right keys to enter the Geometry sub menu.
4. In the Geometry sub-menu, use the Menu Up/Down keys to select VSL.
5. Input a crosshatch pattern to the antenna/cable input terminal.
6. Using the Menu Left/Right keys, adjust VSL so that the squares at the bottom of the screen are equal in size to the squares at the top of the screen.
7. If other Geometry adjustments are needed, proceed to the necessary adjustment using the Menu Up/Down keys.
8. Upon completion of Geometry adjustments, press the Menu button to return to the top level SAM menu.
1. Enter the Service Alignment Mode (SAM) by pressing the following key sequence on the remote control transmitter: 0-6-2-5-9-6-Status
Do not allow the display to time out between entries while keying the sequence.
2. From the top level SAM menu, use the Menu Up/Down keys to highlight the Geometry sub menu.
3. Use the Menu Left/Right keys to enter the Geometry sub menu.
4. In the Geometry sub-menu, use the Menu Up/Down keys to select VSL.
5. Input a crosshatch pattern to the antenna/cable input terminal.
6. Using the Menu Left/Right keys, adjust VSL so that the squares at the bottom of the screen are equal in size to the squares at the top of the screen.
7. If other Geometry adjustments are needed, proceed to the necessary adjustment using the Menu Up/Down keys.
8. Upon completion of Geometry adjustments, press the Menu button to return to the top level SAM menu.
Vertical S-Correction (VSC):
1. Enter the Service Alignment Mode (SAM) by pressing the following key sequence on the remote control transmitter: 0-6-2-5-9-6-Status
Do not allow the display to time out between entries while keying the sequence.
2. From the top level SAM menu, use the Menu Up/Down keys to highlight the Geometry sub menu.
3. Use the Menu Left/Right keys to enter the Geometry sub menu.
4. In the Geometry sub-menu, use the Menu Up/Down keys to select VSC.
5. Input a crosshatch pattern to the antenna/cable input terminal.
6. Using the Menu Left/Right keys, adjust VSC so that the squares at the center of the screen are equal in size to the squares at the top and bottom of the screen.
7. If other Geometry adjustments are needed, proceed to the necessary adjustment using the Menu Up/Down keys.
8. Upon completion of Geometry adjustments, press the Menu button to return to the top level SAM menu.
1. Enter the Service Alignment Mode (SAM) by pressing the following key sequence on the remote control transmitter: 0-6-2-5-9-6-Status
Do not allow the display to time out between entries while keying the sequence.
2. From the top level SAM menu, use the Menu Up/Down keys to highlight the Geometry sub menu.
3. Use the Menu Left/Right keys to enter the Geometry sub menu.
4. In the Geometry sub-menu, use the Menu Up/Down keys to select VSC.
5. Input a crosshatch pattern to the antenna/cable input terminal.
6. Using the Menu Left/Right keys, adjust VSC so that the squares at the center of the screen are equal in size to the squares at the top and bottom of the screen.
7. If other Geometry adjustments are needed, proceed to the necessary adjustment using the Menu Up/Down keys.
8. Upon completion of Geometry adjustments, press the Menu button to return to the top level SAM menu.
Service Blanking (SBL):
Service Blanking provides a straight cutoff line in the center of the
raster. It is useful when centering the raster. It can also be used in
adjusting the yoke and setting vertical size and linearity.
1. Enter the Service Alignment Mode (SAM) by pressing the following key
sequence on the remote control transmitter: 0-6-2-5-9-6-Status
Do not allow the display to time out between entries while keying the sequence.
2. From the top level SAM menu, use the Menu Up/Down keys to highlight the Geometry sub menu.
3. Use the Menu Left/Right keys to enter the Geometry sub menu.
4. In the Geometry sub-menu, use the Menu Up/Down keys to select SBL.
5. Use the Menu Left/Right keys to toggle SBL ON or OFF.
6. With SBL on, VSH can be used to center the raster on the fiduciary
marks (the small notches in the phosphor on the right and left edge of
the CRT). These are absolute center.
7. If other Geometry adjustments are needed, proceed to the necessary adjustment using the Menu Up/Down keys.
8. Upon completion of Geometry adjustments, press the Menu button to return to the top level SAM menu.
Delta HSH for 60Hz (H60):
Note: This adjustment should not be changed from the factory preset value (10).
Delta VAM for 60Hz (V60):
Note: This adjustment should not be changed from the factory preset value (5).
Note: The following GEOMETRY adjustments can only be performed on models containing an East-West Panel (Diode Modulator).
East-West Width (EWW):
1. Enter the Service Alignment Mode (SAM) by pressing the following key
sequence on the remote control transmitter: 0-6-2-5-9-6-Status
Do not allow the display to time out between entries while keying the sequence.
2. From the top level SAM menu, use the Menu Up/Down keys to highlight the Geometry sub menu.
3. Use the Menu Left/Right keys to enter the Geometry sub menu.
4. In the Geometry sub menu, use the Menu Up/Down keys to select EWW.
5. Input a crosshatch pattern to the antenna/cable input terminal.
6. Use the Menu Left key to reduce the value of EWW so that the picture does not fill the entire screen.
7. Use the Menu Up/Down keys to select HSH (Horizontal Shift) from the
Geometry sub menu and, using the Menu Left/Right keys, center the
picture on the screen.
8. Use the Menu Up/Down keys to select EWW from the Geometry sub menu,
and use the Menu Right key to increase the value to obtain a slight
overscan.
Note: Remember, adjusting EWW will affect other horizontal adjustments.
9. If other Geometry adjustments are needed, proceed to the necessary adjustment using the Menu Up/Down keys.
10. Upon completion of Geometry adjustments, press the Menu button to return to the top level SAM menu.
East-West Parabola/Width (EWP):
1. Enter the Service Alignment Mode (SAM) by pressing the following key
sequence on the remote control transmitter: 0-6-2-5-9-6-Status
Do not allow the display to time out between entries while keying the sequence.
2. From the top level SAM menu, use the Menu Up/Down keys to highlight the Geometry sub menu.
3. Use the Menu Left/Right keys to enter the Geometry sub menu.
4. In the Geometry sub menu, use the Menu Up/Down keys to select EWP.
5. Input a crosshatch pattern to the antenna/cable input terminal.
6. Use the Menu Left/Right keys to adjust the value of EWP.
7. This adjusts the top and bottom of the right and left side of the raster, adjusting the raster by “bending” it out or in.
8. This adjustment should be set so that the screen appears to be straight and “flat.”
9. If other Geometry adjustments are needed, proceed to the necessary adjustment using the Menu Up/Down keys.
10. Upon completion of Geometry adjustments, press the Menu button to return to the top level SAM menu.
East-West Trapezium (EWT):
Enter the Service Alignment Mode (SAM) by pressing the following key
sequence on the remote control transmitter: 0-6-2-5-9-6-Status
Do not allow the display to time out between entries while keying the sequence.
2. From the top level SAM menu, use the Menu Up/Down keys to highlight the Geometry sub menu.
3. Use the Menu Left/Right keys to enter the Geometry sub menu.
4. In the Geometry sub menu, use the Menu Up/Down keys to select EWT.
5. Input a crosshatch pattern to the antenna/cable input terminal.
6. Use the Menu Left/Right keys to adjust the value of EWT.
7. This balances the width at the top of the screen to the width at the bottom of the screen.
8. This adjustment should be set so the top and bottom of the screen are of equal width.
9. If other Geometry adjustments are needed, proceed to the necessary adjustment using the Menu Up/Down keys.
10. Upon completion of Geometry adjustments, press the Menu button to return to the top level SAM menu.
East-West Corner Parabola (EWC):
1. Enter the Service Alignment Mode (SAM) by pressing the following key
sequence on the remote control transmitter: 0-6-2-5-9-6-Status
Do not allow the display to time out between entries while keying the sequence.
2. From the top level SAM menu, use the Menu Up/Down keys to highlight the Geometry sub menu.
3. Use the Menu Left/Right keys to enter the Geometry sub menu.
4. In the Geometry sub menu, use the Menu Up/Down keys to select EWC.
5. Input a crosshatch pattern to the antenna/cable input terminal.
6. Use the Menu Left/Right keys to adjust the value of EW CORNER.
7. This adjustment affects the very corner sections of the raster, and
acts as a “touch-up” of the EWP (East-West Parabola/Width) adjustment.
8. This adjustment should be set so the corners of the screen are straight and equal in size.
9. If other Geometry adjustments are needed, proceed to the necessary adjustment using the Menu Up/Down keys.
10. Upon completion of Geometry adjustments, press the Menu button to return to the top level SAM menu.
Audio sub menu
The audio sub menu item values are stored in EEPROM if this sub menu is left.
Attack Time at AVL (AT):
1. Enter the Service Alignment Mode (SAM) by pressing the following key sequence on the remote control transmitter: 0-6-2-5-9-6-Status
Do not allow the display to time out between entries while keying the sequence.
2. From the top level SAM menu, use the Menu Up/Down keys to highlight the Audio sub menu.
3. Use the Menu Left/Right keys to enter the Audio sub menu.
4. Use the Menu Left/Right keys to adjust the value of AT.
5. Set the volume of AT to 4.
6. Upon completion of Audio adjustment, press the Menu button to return to the top level SAM menu.
1. Enter the Service Alignment Mode (SAM) by pressing the following key sequence on the remote control transmitter: 0-6-2-5-9-6-Status
Do not allow the display to time out between entries while keying the sequence.
2. From the top level SAM menu, use the Menu Up/Down keys to highlight the Audio sub menu.
3. Use the Menu Left/Right keys to enter the Audio sub menu.
4. Use the Menu Left/Right keys to adjust the value of AT.
5. Set the volume of AT to 4.
6. Upon completion of Audio adjustment, press the Menu button to return to the top level SAM menu.
Convergence and Purity
Adjustments
Notes:
1. The following adjustments were performed with a Sencore VG91 Universal Video Generator.
2. Set the VG91 Generator as follows: STD TV Ch. 3, RF-IF Range set to HI, RF-IF Level set to NORMAL (1), Video Pattern = Raster, R-G-B raster controls OFF, Mode Switch set to L+R, Audio Frequency set to 300Hz, and 0 Pilot (max. CCW).
3. Connect the RF output of the generator to the Television Antenna Input, and adjust the VG91 level to remove any snow from the raster.
Notes:
1. The following adjustments were performed with a Sencore VG91 Universal Video Generator.
2. Set the VG91 Generator as follows: STD TV Ch. 3, RF-IF Range set to HI, RF-IF Level set to NORMAL (1), Video Pattern = Raster, R-G-B raster controls OFF, Mode Switch set to L+R, Audio Frequency set to 300Hz, and 0 Pilot (max. CCW).
3. Connect the RF output of the generator to the Television Antenna Input, and adjust the VG91 level to remove any snow from the raster.
Pre-Convergence Procedure
Note: The degaussing procedure should be performed prior to this adjustment.
1. Place the multi-pole Purity and Convergence Assembly with the 2-Y pole purity rings directly in the gap between the G2 and G3 (focus) grids as shown in the "Convergence and Purity Assembly" graphic.
2. Enter Service Alignment Mode (refer to Service Alignment Mode section).
3. Apply a center cross or crosshatch pattern to the antenna/cable input terminal.
4. Select the White Tone sub-menu by pressing the Menu Up/Down keys on the remote control so that White Tone is highlighted.
5. Use the Menu Left/Right keys to enter the White Tone sub-menu.
6. Use Menu Up/Down keys to toggle between the options. Be sure to record the values of all options (Normal Red/Green/Blue, Delta Cool Red/Green/Blue, and Delta Warm Red/Green/Blue).
7. Use the Menu Up/Down keys to select Normal Green, and use the Menu Left key to set Normal Green to minimum.
8. Loosen the yoke clamp screw, pull the yoke back, and remove the three yoke wedges.
9. Slide the yoke all the way forward so that it rests against the bell of the CRT.
10 Tighten the yoke clamp screw so that the yoke does not drop away from the bell of the CRT.
11. Slowly spread, and if necessary, rotate the 2-Y pole purity rings so that the red and blue lines are at least parallel and preferably coincide at the 6:00 and 12:00 positions as shown in the "2Y Spread and 2Y Rotate" graphic.
12. Proceed to the Color Purity Adjustment
Note: The degaussing procedure should be performed prior to this adjustment.
1. Place the multi-pole Purity and Convergence Assembly with the 2-Y pole purity rings directly in the gap between the G2 and G3 (focus) grids as shown in the "Convergence and Purity Assembly" graphic.
2. Enter Service Alignment Mode (refer to Service Alignment Mode section).
3. Apply a center cross or crosshatch pattern to the antenna/cable input terminal.
4. Select the White Tone sub-menu by pressing the Menu Up/Down keys on the remote control so that White Tone is highlighted.
5. Use the Menu Left/Right keys to enter the White Tone sub-menu.
6. Use Menu Up/Down keys to toggle between the options. Be sure to record the values of all options (Normal Red/Green/Blue, Delta Cool Red/Green/Blue, and Delta Warm Red/Green/Blue).
7. Use the Menu Up/Down keys to select Normal Green, and use the Menu Left key to set Normal Green to minimum.
8. Loosen the yoke clamp screw, pull the yoke back, and remove the three yoke wedges.
9. Slide the yoke all the way forward so that it rests against the bell of the CRT.
10 Tighten the yoke clamp screw so that the yoke does not drop away from the bell of the CRT.
11. Slowly spread, and if necessary, rotate the 2-Y pole purity rings so that the red and blue lines are at least parallel and preferably coincide at the 6:00 and 12:00 positions as shown in the "2Y Spread and 2Y Rotate" graphic.
12. Proceed to the Color Purity Adjustment
Color Purity Adjustment
1. Connect a solid white pattern signal to the antenna/cable input terminal.
2. Use the Menu Up/Down keys to select Normal Blue, and use the Menu Left key to set Normal Blue to minimum.
3. Use the Menu Up/Down keys to select Normal Red, and use the Menu Right key to set Normal Red to maximum.
4. Slowly spread the 2-X pole purity rings to center the red portion of the screen, leaving the same amount of green on one side of the screen as blue on the other side.
5. Tighten the yoke clamp screw slightly so that the yoke may be moved with some friction.
6. Proceed to the Static Center Convergence Adjustment.
Static Center Convergence Adjustment
1. Apply a center cross or crosshatch pattern to the antenna/cable input terminal and observe the screen to ensure that the yoke is not tilted. If necessary, rotate the yoke to obtain a level raster.
2. Use the Menu Up/Down keys to select Normal Blue, and use the Menu Right key to set Normal Blue to maximum.
3. Slowly spread, and if necessary, rotate the 4-pole magnetic rings to converge red and blue lines at the center of the screen.
4. Use the Menu Up/Down keys to select Normal Green, and use the Menu Right key to set Normal Green to maximum.
5. Slowly spread, and if necessary, rotate the 6-pole magnetic rings to converge red/blue on green lines at the center of the screen.
6. Repeat steps three and five for optimum performance.
7. Proce (Display Convergence and Purity Assembly)
Dynamic Edge Convergence Adjustment
Note: To secure the correct position of the deflection yoke, three rubber wedges are used.
1. Connect a solid white pattern signal to the antenna/cable input terminal.
2. Use the Menu Up/Down keys to select Normal Blue, and use the Menu Left key to set Normal Blue to minimum.
3. Use the Menu Up/Down keys to select Normal Red, and use the Menu Right key to set Normal Red to maximum.
4. Slowly spread the 2-X pole purity rings to center the red portion of the screen, leaving the same amount of green on one side of the screen as blue on the other side.
5. Tighten the yoke clamp screw slightly so that the yoke may be moved with some friction.
6. Proceed to the Static Center Convergence Adjustment.
Static Center Convergence Adjustment
1. Apply a center cross or crosshatch pattern to the antenna/cable input terminal and observe the screen to ensure that the yoke is not tilted. If necessary, rotate the yoke to obtain a level raster.
2. Use the Menu Up/Down keys to select Normal Blue, and use the Menu Right key to set Normal Blue to maximum.
3. Slowly spread, and if necessary, rotate the 4-pole magnetic rings to converge red and blue lines at the center of the screen.
4. Use the Menu Up/Down keys to select Normal Green, and use the Menu Right key to set Normal Green to maximum.
5. Slowly spread, and if necessary, rotate the 6-pole magnetic rings to converge red/blue on green lines at the center of the screen.
6. Repeat steps three and five for optimum performance.
7. Proce (Display Convergence and Purity Assembly)
Dynamic Edge Convergence Adjustment
Note: To secure the correct position of the deflection yoke, three rubber wedges are used.
1. Apply a crosshatch pattern to
the antenna/cable input terminal.
2. Use the Menu Up/Down keys to select Normal Green, and use the Menu Left key to set Normal Green to minimum.
3. Tilt the yoke up and down to converge the red and blue vertical lines at the 6:00 and 12:00 positions and the red and blue horizontal lines at the 3:00 and 9:00 positions (refer to Figure 5 ). When the correct position has been found, place a rubber wedge between the yoke and the CRT. If the yoke is tilted up, place wedge one as shown in Figure 3a; if it is tilted down, place wedge one.
4. Tilt the yoke to the left and right to find the point of best possible convergence of the red and blue lines at the edges, top and bottom of the screen.
2. Use the Menu Up/Down keys to select Normal Green, and use the Menu Left key to set Normal Green to minimum.
3. Tilt the yoke up and down to converge the red and blue vertical lines at the 6:00 and 12:00 positions and the red and blue horizontal lines at the 3:00 and 9:00 positions (refer to Figure 5 ). When the correct position has been found, place a rubber wedge between the yoke and the CRT. If the yoke is tilted up, place wedge one as shown in Figure 3a; if it is tilted down, place wedge one.
4. Tilt the yoke to the left and right to find the point of best possible convergence of the red and blue lines at the edges, top and bottom of the screen.
6. When the correct position is located, place
wedges two and three.
5. Remove wedge one and place it in the final position.
6. Use the Menu Up/Down keys to select Normal Green, and use the Menu Right key to set Normal Green to maximum.
7. Proceed to the White Balance Setup.
Master Screen (VG2)/ White Balance Setup:
1. With the set OFF, rotate VG2 (located on the lower part of the flyback transformer) counterclockwise.
2. Use the Power Button (on the remote control or the local keyboard) to turn the set ON, without a signal, and rotate VG2 clockwise until snow is visible.
3. Enter Service Alignment Mode (SAM).(refer to Service Alignment Mode section).
4. Enter the Virtual Customer Menu by pressing the Menu button on the remote and set brightness and picture to 31 and color to 0.
5. Apply an NTSC color bar signal to the antenna/cable input terminal and tune to the active channel.
6. Connect an oscilloscope, 20V per division and 10 uSec time base, to pin 6 of the CRT Socket. Observe the stairstep pattern while adjusting VG2.
Hint: Counterclockwise adjustment will compress bottom of stairstep pattern.
Clockwise adjustment will compress top of stairstep pattern.
7. Adjust VG2 midway between top and bottom compression.
8. Proceed to White-Tone Adjustments under White Tone sub-menu in the Service Alignment Mode section to complete White Balance Setup.
5. Remove wedge one and place it in the final position.
6. Use the Menu Up/Down keys to select Normal Green, and use the Menu Right key to set Normal Green to maximum.
7. Proceed to the White Balance Setup.
Master Screen (VG2)/ White Balance Setup:
1. With the set OFF, rotate VG2 (located on the lower part of the flyback transformer) counterclockwise.
2. Use the Power Button (on the remote control or the local keyboard) to turn the set ON, without a signal, and rotate VG2 clockwise until snow is visible.
3. Enter Service Alignment Mode (SAM).(refer to Service Alignment Mode section).
4. Enter the Virtual Customer Menu by pressing the Menu button on the remote and set brightness and picture to 31 and color to 0.
5. Apply an NTSC color bar signal to the antenna/cable input terminal and tune to the active channel.
6. Connect an oscilloscope, 20V per division and 10 uSec time base, to pin 6 of the CRT Socket. Observe the stairstep pattern while adjusting VG2.
Hint: Counterclockwise adjustment will compress bottom of stairstep pattern.
Clockwise adjustment will compress top of stairstep pattern.
7. Adjust VG2 midway between top and bottom compression.
8. Proceed to White-Tone Adjustments under White Tone sub-menu in the Service Alignment Mode section to complete White Balance Setup.
Customer Service Mode (CSM)
1. The Customer Service Mode (CSM) is used to retrieve data on the TV operation settings and stored error codes.
2. To enter the Customer
Service Mode, press and hold the Mute button on the remote control and
any key on the local keyboard (except ”Power“) for more than 4 seconds.
When the set is in Customer Service Mode, the text "CSM" is displayed in
the top right corner of the screen.
3. To use this system,
the customer is instructed by phone to enter CSM and read off the
display that appears. This information is useful to gain insights into
failures before traveling to the customer's home.
4. This information can
also be used to avoid nuisance trips to the home when the problem is an
operational error (example: Closed Caption is on or set is in Hospital
Mode).
5. When entering CSM,
all disruptive functions are turned off, and service unfriendly modes
are ignored. While CSM is active, no changes can be made in settings or
functions. When CSM is exited, the TV returns to all prior operational
settings.
6. To exit CSM, press any key (on the remote control or local keyboard) except ”Channel Up“ or ”Channel Down.“
To
exit CSM and return the set to normal operation mode, press any key on
the local keyboard or the remote control except Channel Up, Channel
Down, or Power.
To exit CSM and turn the set off, press the Power button on either the TV set or
the remote control.
Explanation of CSM Display Screen
The following information is displayed on screen:
• Text ”CSM“ on the first line
• Line number for every line (to make CSM language independent)
• To view multiple CSM pages (such as lines 8 and 9), use the Channel Up or Channel Down keys
• For more information on lines 1, 2, and 3, see SDM section ”Explanation of Display“
• Line 1 displays the run timer and the software identification, cluster, and version
• Line 2 displays the error buffer contents (the word ”error“ is not used on this screen, instead ”codes“ is used)
• Line 3 displays the option code information
• Line 4 displays SYS: (This is not used)
• Lines 5 through 8 display information on active service unfriendly modes
• Line 5 displays the text ”NOT TUNED“ if no television station is tuned
• Line 6 displays the text ”TIMER“ if the sleep timer or ”on“ timer is active
• Line 7 displays the text ”LOCKED“ if one or more channels or presets is locked via child lock
• Line 8 displays the text ”HOSPITAL“ if hospital mode is active, or ”HOTEL“ if hotel mode is active
• If the volume limiter
is active, line 9 displays the text ”VOL LIM“ and the set value of the
volume limiter. If the volume limiter is inactive, the displayed value
will be 255 (the maximum volume allowed)
