Medion B1997PNST Manuel de service télécharger pdf (Page 19)

Page 17

Alignments and Adjustments

MD 1998LE (B1997PNST)

Note : The 4-pole magnets and the 6-pole magnets interact, making dot movement complex.

4-2-5 Degaussing

Degaussing is required when poor color impurity appears on the screen. This monitor uses an automatic

degaussing circuit that is activated when the power is on. The manual degaussing will be fully functional after

the monitor has been in operation for 20 minutes through OSM degaussing function.

The degaussing effect is confined to the picture tube since the coils are mounted at the back of the tube.

Should any part of the chassis or cabinet becomes magnetized, it is necessary to degauss the affected area

with a external degaussing coil.

4-2-6 External Degaussing

1. Apply line voltage to the degaussing coil and move it in a rotary motion over the front, sides, and top of the

monitor. The coil should be kept away from the rear of the monitor to avoid damaging the magnetic neck

components.

2. Slowly rotate and move the coil away from the monitor to about 6 feet beyond the point where no effect

on the CRT will be noticeable.

For proper degaussing, it is essential that the field be gradually reduced by moving the coil slowly away from

the monitor. The degaussing coil must never be shut off or disconnected while near the monitor, as this would

introduce a strong field instead of canceling the effect of the stray fields.

Figure 4-2. 4-pole and 6-pole Magnets Movement

Blue Red

Blue

Red

Red/

Blue Green

Red/

Blue

Green

4-pole magnets

movement

6-pole magnets

movement

1 2 ... 14 15 16 17 18 19 20 21 22 23 24 25 26 27

Pas de commentaire

Medion B1997PNST Manuel de service Page 19