Sony KV-HF21M80 service manual Focus Adjustment, G2 Screen and White Balance Adjustments

(3) Screen-corner Convergence

ba

a-d : screen-corner misconvergence

cd

Fix a Permalloy assy corresponding to the misconverged areas.

Fix a Permalloy assy	b
corresponding to the
misconverged areas
a

	c
d	a to d : Permalloy assembly

3-3. FOCUS ADJUSTMENT

Adjust FOCUS control on the flyback transformer for the best

focus.

FOCUS

SCREEN

FLYBACK TRANSFORMER (T503)

KV-HF21M80

RM-952

3-4. G2 (SCREEN) AND WHITE BALANCE

ADJUSTMENTS

1. G2 (SCREEN) ADJUSTMENT

1)Set the PICTURE to normal.

2)Put to VIDEO input mode without signals.

3)Connect R, G and B of the C3 board cathode to the oscillo- scope.

4)Adjust BRIGHTNESS to obtain the cathode voltage to the value below.

5)Adjust G2 (Screen) on FBT until picture shows the point before cut-off.

175 V ± 2(VDC)

0 V

2. WHITE BALANCE ADJUSTMENT

1)Set to Service Mode (Refer Section 5-1: ADJUSTMENTS WITH COMMANDER).

2)Input white raster signal.

3)Set the PICTURE to minimum.

4)Select GCT (WHB 4) and BCT (WHB 5) with [1] and [4], and adjust the level with [3] and [6] for the best white balance.

5)Set the PICTURE to maximum.

6)Select GDR (WHB 1) and BDR (WHB 2) with [1] and [4], and adjust the level with [3] and [6] for the best white balance.

7)Write into the memory by pressing [MUTING] then [0].

3. SUB BRIGHT ADJUSTMENT

1)Set to service mode.

2)Input a staircase signal of black to white from the pattern generator.

3)BRIGHTNESS .... 50%. PICTURE ............ MINIMUM

4)Select SBR (WHB7) with [1] and [4], and adjust SBR (WHB7) level with [3] and [6] so that the second stripe from the right is dimly lit.

White

second from the right

Black

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