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TC-20G12P / TC-29G12P / TC-29G12PU
Service Adjustments and Calibrations
ELECTRICAL INSPECTIONS
REQUIRED EQUIPMENTS / CONNECTIONS:
Voltmeter 150VDC: between C809 (+) and Ground HOT(-).
RMS Voltmeter: CRT Heater Terminal.
PROCEDURE:
1. Apply a PHILIPS pattern.
2. Adjust AC supply to 110 or 220 V. Adjust BRIGHT and
CONTRAST control until get a totally black screen. The
DC Voltmeter must be 130V±2.5V.
3. The heater terminal voltage must be:
TC-20G12P→6,15V+0.40Vrms _0.24Vrms
TC-29G12P/TC-29G12PU→6,3V+0.40Vrms _0.24Vrms
DEFLECTION CIRCUIT PRE-ADJUSTEMENTS
REQUIRED EQUIPMENTS / CONNECTIONS:
Voltmeter (50KV): Connect between CRT anode and CRT
DAG GROUND.
PROCEDURE:
1. Apply a PHILIPS pattern.
2. Adjust VERTICAL HEIGHT (DAC B:5) until get a circle.
3. Apply a CROSSHATCH pattern.
4. Adjust BRIGHT and CONTRAST control until get a totally
black screen. The voltage on Voltmeter must be:
TC-20G12P→26,25kV±1,25kV
TC-29G12P/TC-29G12PU→29,1kV+1.4kV_1.5kV
5. Apply a PHILIPS pattern and readjust the BRIGHT and
CONTRAST control to get a correct image picture.
6. Adjust the HORIZONTAL CENTER (Cc register) until
the image is correctly centered.
To TC-29G12P and TC-29G12PU only:
7. Confirm that the horizontal width is in normal range.
8. Correct E-W Pincushion by adjusting R761 in the Z-PCB.
9. Correct the horizontal width by adjusting R760 in the Z-PCB.
AGC CIRCUIT PRE-ADJUSTMENTS
REQUIRED EQUIPMENTS / CONNECTIONS:
Oscilloscope: TP2.
PROCEDURE:
1. Apply a 63dB±2dB pattern signal (75Ω open)
(Using a high VHF channel 7 ~ 13).
2. Set the CONTRAST control on center position.
3. Verify the CONTRAST variation with SUB-CONTRAST
(DAC B:3) to get a 3.0Vp-p wave form on the oscilloscope
at TP2.
4. Verify if snow appear when the RF AGC register
(DAC:Ca) is decreased. Then increase it slowly until the
snow has disappeared.
WHITE BALANCE ADJUSTMENTS
REQUIRED EQUIPMENTS / CONNECTIONS:
Oscilloscope: Connect to CRT board GK and ground.
PREPARATION:
1. Get turn ON the equipment for about 15 minutes.
2. Set standard WHITE BALANCE.
3. Adjust the image mode to DYNAMIC.
4. Fix the COLOR adjust in NORMAL.
5. Fix the CONTRAST adjust in NORMAL.
6. Enter in the service mode.
7. Adjust CUT OFF and DRIVE DATA to:
C0: CUT OFF_R= 0_64
C1: CUT OFF_G= 0_128
C2: CUT OFF_B= 0_64
C3: DRIVER_R= 64
C4: DRIVER_B= 64
8. Adjust SCREEN VR to minimum.
9. Connect the oscilloscope.
PROCEDURE:
1. In Service Mode, press R-TUNE on remote control to
enter in the Horizontal Line mode.
2. Look (GK) on the oscilloscope, then adjust SUB-BRIGHT
(DAC:B2) until the raster period be as the draw bellow.
3. Adjust SCREEN VR to the first line stayed lightly
illuminated.
Note: After adjust, the SCREEN VR doesnt must be
moved.
4. Adjust CUTT OFF to the horizontal line become white.
(R,B CUT OFF) (DAC: C0) (DAC: C2).
5. Press again R-TUNE to exit of Horizontal Line mode.
6. Get appropriate White Balance moving the REC drive
(DAC: C3) and BLUE drive (DAC: C4).
7. Apply a PHILIPS pattern.
8. Get a normal image adjusting CONTRAST, BRIGHT
and FOCUS VOLUME controls. Then confirm the image
doesnt show serious convergence loss.
GK waveform
TC-20G12P = 160VDC
TC-29G12P = 195VDC
TC-29G12PU = 195VDC
3Vp-p
Excluding the eraser part