Panasonic TC-14A12P, TC-20B12 service manual CRT CUT OFF Calibration

TC-14A12P / TC-20B12

Service Adjustments and Calibrations

5.VERTICAL HEIGHT (V-AMP 50HZ) CALIBRATION

5.1.Receive a PAL-N Philips pattern.

5.2.Adjust V-AMP-50Hz so that the Philips pattern’s circle height be the same dimension of the width.

6.VERTICAL HEIGHT (V-AMP 60HZ) CALIBRATION

6.1.Receive a monoscope pattern.

6.2.Adjust V-AMP-60Hz so that:

[C]and [D] (see below) be 1.9~2.2 (typical 2.0) for 14 inches and 1.5~2.0 for 20 inches.

[A]and [B] be 1.5~2.3 (typical 2.0) for 14 inches and 1.5~1.6 for

20 inches.

6.3. Memorize in EEPROM.

AB

C D

CRT CUT OFF CALIBRATION

1. PREPARATION:

1.1.Receive a monoscope pattern.

1.2.Position DACs with the data below:

•BRT AND S-BRT = 32H.

•RGB CONTRAST = 06H for 14 inches and 07H for 20 inches.

•SUB-CONTRAST = 21H

•R,G,B DRIVE = 31H

•R,G CUT = 31H

1.3.Press “5” (AKB OFF) and confirm that OSD becomes blue.

1.4.Connect the oscilloscope in TPL7 and adjust BRT to obtain 130V in the figure below.

1.5Adjust screen to minimum.

130V

0V

1.6. Press “5” (AKB ON) and confirm that OSD becomes white.

2. CALIBRATION:

[1]LOW LIGHT CALIBRATION

1.Adjust S-BRT, so that Y = Y(L).

2.Adjust R-CUT OFF, so that x = x(L).

3.Adjust G-CUT OFF, so that y = y(L).

[2]HIGH LIGHT CALIBRATION

1.Adjust S-BRT, so that Y = Y(H).

2.Adjust R-DRIVE, so that x = x(H).

3.Adjust B-DRIVE, so that y = y(H).

[3]Repeat the procedures [1] and [2].

SUB-BRIGHTNESS CALIBRATION

1. PREPARATION:

1.1.Receive a windows pattern.

1.2.Position MENU OF IMAGE in DYNAMIC NORMAL.

2. CALIBRATION:

2.1.Position the color analyzer in an low light image area of CRT.

2.2.Adjust S-BRT <CHK 5>, so that Y=5.5 ± 0.2.

SUB-CONTRAST CALIBRATION

1.PREPARATION:

1.1.Receive a windows pattern.

1.2.Position MENU OF IMAGE in DYNAMIC NORMAL.

2. CALIBRATION:

2.1.Position the color analyzer in an hight light image area of CRT. 2. Adjust the SUB-CONTRAST <CHK 4>, so that Y=300±10 for 14 inches and Y=160±10 for 20 inches.

3. If it is impossible to obtain the adjustment above, adjust the SUB-CONTRAST <CHK 4> and confirm the SUB-BRIGHTNESS adjustment.

FOCUS CALIBRATION

1.PREPARATION:

•Assure that the SUB-BRIGHTNESS adjustment has been done.

1.1.Receive a Philips or monoscope pattern.

1.2.Position MENU OF IMAGE in DYNAMIC NORMAL.

2. CALIBRATION:

2.1. Adjust the FOCUS variable resistor.

WHITE BALANCE CALIBRATION

1. PREPARATION:

1.1.This adjustment should be accomplished after 30 minutes of heating.

1.2.Receive a white balance. (This sign should contain burst sign).

1.3.Position DAC of MENU OF IMAGE for DYNAMIC NORMAL.

1.4.Fully degauss the CRT by using an external degaussing coil.

1.5.Position the color analyzer in contact with the face of CRT.

•Assure that the CUT OFF voltage calibration has been done.

•If the value in the color analyzer is below Y(H) date, adjust CONTRAST for 32 and connect a short circuit jumper between TPA10 and TPA20.

Using the Philips pattern:

•Take as reference to 3rd vertical line.

1 2 3 3 2 1

Using the monoscope pattern:

• In the number 4

4

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