SECTION 5

CIRCUIT ADJUSTMENTS

5-1. RF AGC

1.Input a color-bar signal.

2.Adjust AGC VR of TU1101 so that snow noise, and crossmodulation disapper from the picture.

3.Verify picture quality on each channel.

5-2. BER DISPLAY ADJUSTMENT (DISP)

1.Receive the cross-hatch signal.

2.Set to Service mode.

3.Select “ DISP ”, and adjust so that the blank spaces on the both sides of picture bar become equal.

4.Write the data into memory. MUTING n ENTER

5-4. SUB-HUE AND SUB-COLOR ADJUSTMENT (SHUE, SCOL)

1.Receive the color-bar signal.

2.PICTURE : maximum

COLOR : minimum

BRIGHTNESS : minimum

3.Set to service mode.

4.Connect an oscilloscope between 7 pin of CN004 (A Board) connecter and ground.

5.Select “ SHUE ” and “ SCOL ”, and adjust them to have VB1 = VB4 and VB2 = VB3 in the waveform levels.

6.Raise SCOL data 1 steps higher.

7.Write the data into memory. MUTING n ENTER

A

A=B

B

Fig. 5-1

5-3. SUB CONTRAST ADJUSTMENT (SCON)

1.Receive the color-bar signal.

2.PICTURE : maximum

COLOR : minimum

BRIGHTNESS : minimum RON---1 GON---0 BON---0

3.Set to service mode.

4.Connect an oscilloscope between 6 pin of CN004 (A board) and ground.

5.Select “ SCON ”, and adjust so that the wave from level is 1.65±0.05Vp-p.

6.Write the data into memory. MUTING n ENTER

White

1.65 ± 0.05Vp-p

Black

Fig. 5-2

VB1 VB2 VB3 VB4

Fig. 5-3

5-5. P IN P POSITION ADJUSTMENT (PIPH, PIPV)

1.Receive the monoscope signal.

2.Set to P IN P () mode, and to Service mode.

3.Check the SUB PICTURE position.

4.Select “ PIPH ” and “ PIPV ” and adjust H/V position to the center level.

5.Write the data into memory. MUTING n ENTER

V

H

H : 7.00 ± 0.25sq

V : 5.25 ± 0.25sq

Fig. 5-4

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Sony KP-41T65C service manual Rf Agc, BER Display Adjustment Disp, SUB-HUE and SUB-COLOR Adjustment SHUE, Scol