Wednesday, November 02, 2016

Konka KDT143AST how to enter service mode – adjustments - Color Television Receiver

ALIGNMENT PROCEDURES
1. Use an Isolation Transformer when performing any service on this chassis.
2. Never disconnect any leads while receiver is in operation.
3. Disconnect all power before attempting any repairs.
4. Do not short any position of the circuit while the power is on.
5. For safety reasons, replace components any with identical replacement parts (SEE PARTS LIST).
6. Before alignment, warm up the TV for at least 30 minutes and demagnetize the CRT with an external degaussing coil.
7. When removing a PCB or related component, after unfastening or changing a wire, be sure to put the wire back in its original position.
8. Inferior silicon grease can damage IC's and transistors. When replacing IC's and transistors, use only specified silicon grease. Remove all old silicon when applying new silicon.
9. Before removing the anode cap, discharge electricity because it contains high voltage.

Service Flow Chart
Power supply
Check input voltage > check voltage of C910 anode > check Pin 4 of N901(17v) > check N901 > check output voltage of T901 secondary coil > check voltage of N931,N933 Pin 3(5.0v) and N932 Pin3 (9.0V) > check voltage of N103 Pin 3,15,45(5v) and Pin25,54 (3.3v)
Audio circuit
check power supply of audio power amplify circuit(21V) > check input audio signal of audio power amplifier circuit > check waveform of XS203 Pin1 
Horizontal circuit 
Check voltage of C960 anode 108V > check waveform of V401 Base > check waveform of V402 Collector > check output voltage of T402 coil > check waveform of T402 Pin 8.
Vertical circuit:
check voltage of C963 anode +12V ,C964 anode –12V > check waveform of N103 Pin 34 Pin35 > checkwaveform of N440 Pin 1 Pin7 > check waveform of N440 Pin 5.
UOC circuit:
check voltage of N103 Pin 7 (5v) and Pin32 (0v) > check Pin6 (5v) > check waveform of N103 Pin31.
1. Follow the pointed test steps and choose the right test equipment to conduct adjustment, otherwise good effect of the unit could not be obtained. Pointed bias voltage value should be ensured during test to get satisfied test result.
2. To adjust the chassis, before installing, you should write mother chip’s data into the memory N104 that being installed into this chassis and no any data except this test manual listed are promised to be modified.
3. Let the unit warm up at least 30 minutes and demagnetize the CRT and cabinet with degaussing coil before testing.
Test equipment
1. Oscilloscope
2. Voltmeter
3. Multimeter( Inside resistance: DC≥20kΩ/V, AC≥5kΩ/V)
4
.High Voltmeter 40kV
5. Degaussing Coil
6
.PHILIPS Pattern Signal Generator (PH5820)
IF adjustment
1 Disconnect IF end of RF Tuner.
2 Apply 8V stable power supply to N931(7805) and N933(7805)input point.  Apply 12V stable power supply to N932(7809) input point.
3 Adjust RP121 to the middle position, then swap TV system to PAL D/K with remote control, connect PH5820 to IF input (R101 and C101 joint) and apply 95dB 38.9MHz PAL D/K signal.
4 Connect oscilloscope or digital voltmeter anode to Pin8 of N103, and cathode to GND, adjust IFT T101 with non-inductive rod until the measured point level reading on the voltmeter is 1.60±0.05V.(Core inside IFT)
5. Reconnect IF end of RF tuner after adjustment.
HF AGC adjustment
1 Receive signal (U channel)
2 Set input field strength to 60dBμV (PAL D/K)gray scale signal.
3 Adjust RP120 until C119 anode is just 4.0V±0.1V.
Factory menu (Service Mode)
1. Press MENU button to display the main menu, then press RECALL button five times continuously to enter factory mode.
Press 0 button, then RECALL button to exit factory mode.
2. After entering factory mode:
Press 1 button to adjust Horizontal: including HBLANK
HBS0,HBS0,H-POSITIONHPOS),H-SIZEH-P0, H TRAPEZIUMHP1 ), H PINCUSION( H-P2 ), H S-CORRECTION( H-P3 ), H E-W CORNER CORRECTION(H-P4)
Press 2 button to adjust Vertical
including V PHASE(OFS),HEIGHT(VP1),V SYMMETRY(V-P2),V LINEARITY(V-P3),Angle, Bow adjustment are also Vertical adjustment.
Angle adjustment: no upper adjustment, just switch the lower right and left to adjust.
Bow adjustment: no upper adjustment, just switch the lower right and left to adjust.
Press 3 button: Select some functions
Press 4 button
Check DRIVE REF.
Press 5 button
Enter into G2 mode.(This mode is for grid test)
Press 6 button
Check CUTOFF.
Press 7 button
Select some functions
Press 8 button
Brightness/ Contrast/Color parameters setting
Press 9 buttonMemory data.
3
Press PROG./PROG. to select test item, and VOL+/- button to adjust the value, then press RECALL button to confirm and store.
Geometry Distortion adjustment
Adjust Geometry Distortion under factory mode with remote control including: V PHASE, V SYMMETRY, V LINEARITY, H PHASE, H SIZE, H PINCUSHION, etc. RECALL must be pressed after every step finishing to store, and the adjustment must be done according to the following order.
Use 50Hz Circle Test Card with CENTER CROSS pattern as test signal, then use remote control to enter factory mode.
1) Press 1 button to adjust Hor Blanking Stop/Start until H Blank is just out the screen.
2 ) 
Vertical Phase adjustment: Press 2 button to adjust VERT Position value until V-center and the screen’s geometric center is in accordance.
3 ) V AMPLITUDE adjustment: Select Vert Amplitude item to adjust the vertical amplitude until it is at an ppropriate position.
4)
 adjustment, select S-Correction item and adjust it to make the upper and lower picture symmetrical.
5
)V-Linearity adjustment: Select Vert S-Symmetry item, adjust the value to make the vertical distance from upper edge to middle pattern is equal to the vertical distance from lower edge to middle pattern.
6
)Press 1 button to adjust horizontal center: Adjust Hor Position item until pattern V-center and the screen’s geometric center is in accordance.
7) Select AV mode and use 60Hz Circle Test Card with CENTER CROSS pattern as test signal, then use remote control to enter factory mode and select vertical distortion menu. Adjust 60Hz Geometry Distortion according to steps 16.
Repeat steps from (1) to (7) until the right value is obtained.
Functions for this unit (Select different functions for different models) Enter into factory mode, then press 3 button to select and adjust as the following:
Contents in factory menu 3
Teletext
Yes
Child Lock: Yes
Alps Used
Yes
Avout Fixed: Yes
Hdev3 used
No
White Line: (It should be closed in white balance adjustment)
Press button -/--,select and adjust according to the following order:
RemoteMode:KK-DVD
Ycbcr(AV): Yes
Cvbs2: No
SVHS: No
Side AV: Yes
SCARTGrid/Focus adjustment.
1. Set condition is AV mode without signal and enter into factory menu,press 5 button to adjust the brightest color line of R, G and B just appears on the screen. Exit the factory menu.
2. Select CROSSHATCH and DOT signal, then set PICTURE to STANDARD mode.
3. Adjust FOCUS to make the picture on the CRT is the clearest (RGB).
Sub Brightness adjustment
Select black and white five circles pattern, set PICTURE to standard mode. Enter into factory menu, then press 8 button to adjust Bright Mid until 8~8.5 gray scale of 10 gray scale appears on the screen. (Recommend value is 25~35). Exit factory menu.
White balance adjustment
1 Apply “left black right white” signal for white balance adjustment.
2 Enter into factory menu with remote control, press EQU button to display CCU OFF character.
3 Insert I2C BUS controller plug that is used for automatic adjustment system into XS600 socket on the main board.
4 Run the program.
5 Press SPACE key or press switch on the controller socket, white balance adjustment will be operated automatically. There have three color temperature for you to adjust, if OK, “Click” will be heard.
6 Unplug I2C controller after adjustment finishing, then press CLOCK button on the remote control to restore CCU ON.
Standard:Color temperature 9300K (X=0.284 Y=0.299)
Cold color:Color temperature 12000K(X=0.272 Y=0.279)
Warm color:Color temperature 6500K (X=0.313 Y=0.329).
Press 7 button and adjust as the following order:
MSP Enable: Yes
VOL 01(19):25
VOL 10(39):85
VOL 40(99):110
VOL 70: 115
VOL 99: 125
Memory check
Enter into factory menu, press 8 button to confirm the following settings.
2. Press 9 button to check every address data in E2PROM. address=0~511 in memory can not be changed at will and the following data should be right.)
Click on the tables to magnify
Different data(Select corresponding data according to different model)
Key point voltages
Note: Cold ground is regarded as the reference point for these measured data if no any other explanation being made.
“-” presents the X Pin of the component(for example: N101-12 presents The 12th Pin of N101).
fig-5&6
FBT Voltage: Tube data ( the following voltage value are the reference voltage.)