Panasonic TC-21Z80PQ, Руководство по обслуживанию

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4.2. Colour Purity
1. Set Bright and Contrast controls to their maximum
positions.
2. Operate the TV set over 60 minutes.
3. Full degauss the picture tube by using an external
degaussing coil. By rotating R-B static convergence
magnet.
4. Apply a crosshatch pattern signal and adjust roughly the
static convergence magnets.
5. Apply a green pattern signal.
6. Loosen a clamp screw for the Deflection Yoke and move
the Deflection Yoke as close to the purity magnet as
possible.
7. Adjust the purity magnet so that a vertical green field is
obtained at the center of the screen.
8. Slowly press the Deflection Yoke and set it where a uniform
green field is obtained.
4 ADJUSTMENT PROCEDURE
4.1. Adjustment Procedure
Item / Preparation Adjustment Procedure
+B Voltage Confirm the DC voltage at the indicated test points, as follows :
1. Operate the TV set. TPA 10 : 141.0 ± 1.5V
2. Set control as follows : TPA 8 : 8 ± 1V
Brightness ........... minimum TPA 9 : 5 ± 1V
Contrast .............. minimum TPA 21 : 215 ± 15V
RF AGC
1. Receive a colour bar signal at an RF level of 69
+1-2 dBU with 75
Ω
loaded.
1. Select “RF AGC” indication in CHK2, on Screen by remote control at factory
mode.
2. Connect digital multimeter to RF AGC at Tuner. 2. Set RF AGC by using remote control Volume (+) or Volume (-) button until voltage
AGC at Tuner reaches 2.6 ± 0.1V at TPA 15 (Tuner point).
3. Increase RF signal strength by 2dB, confirm AGC at Tuner voltage drop.
High Voltage
1. Receive the crosshatch pattern. 1. Connect a DC voltage meter to TPA 12 and confirm the +B voltage is 141.0 ±
1.5V.
2. Set to 0 Beam.
Screen VR .......... minimum 2. Connect a high frequency voltmeter to heater and confirm that voltage reads 6.3
± 0.24 (VRMS).
Contrast .............. minimum
3. Normalize the brightness and contrast.
Item / Preparation Adjustment Procedure
NTSC TINT COLOUR
Connect oscilloscope probe to TPL1 (R OUT) with
10k
Ω
series resistor.
Press Main Menu and set system to use AV-NTSC
(3.58 MHz).
DYNAMIC................. Normal
Channel CLR Set ..... STD
1. Adjust Sub-Tint so that No. 2, 3 and 4 becomes level waveform is similar to Fig.
3.
2. Confirm phase at Tint is changes more than ± 15 by Tint control.
3. Confirm that colour level is maximum when colour DAC is adjusted to maximum
position.
Note: Use remote control only when adjusting user mode to Sub-Tint.
Fig. 3
7
TC-21Z80PQ