JVC AV21L91(BK)
Service Manual

AV-25L91

STATIC CONVERGENCE ADJUSTMENT [AV-25L91-BK]
1. Input a crosshatch signal. 2. Using 4-pole convergence magnets, overlap the red and blue lines in the centre of the screen (Fig. 7) and turn them to magenta (red/ blue). 3. Using 6-pole convergence magnets, overlap the magenta(red/blue) and green lines in the centre of the screen and turn them to white.
(FRONT VIEW) (FRONT VIEW)

Fig. 7

4. Repeat 2 and 3 above, and make best convergence.

TOP

DYNAMIC CONVERGENCE ADJUSTMENT [AV-25L91-BK]
BOTTOM

1. Move the deflection yoke up and down to adjust the pin cushion distortion in the screen top and bottom. (Fig. 8)
(FRONT VIEW)

Fig. 8

2. Using the YV VR on the deflection yoke, match the YV. (Fig. 9)
RED

GREEN BLUE YV BLUE

GREEN RED RED GREEN BLUE

3. Using the YH VR on the deflection yoke, match the YH (CROSS). (Fig. 7 and 12) 4. Repeat the steps 1 and 3 and obtain an optimum convergence. 5. Differential coil ADJUSTMENT. In case where the horizontal lines of red and blue around the centre of both sides of the picture as shown in Fig. 11, adjust the XV difference by using the differential coil on the top of the deflection yoke (Fig. 12) so as to minimize the XV difference.

BLUE GREEN RED YV Fig. 9 (FRONT VIEW) RED YH GREEN BLUE

� After adjustment, fix the wedge at the original position.
Fasten the retainer screw of the deflection yoke. Fix the 6 magnets with glue.

RED GREEN

RED GREEN BLUE

YV VR

YH VR

BLUE

BLUE

GREEN YH

RED

FRONT XV coil
(FRONT VIEW) Fig. 10

Fig. 12

Xv

GREEN

Fig. 11

46

No. 51898