LG Electronics 30FZ4D, 32FZ4D-UA service manual ¯ Convergence Adjustment

PURITY & CONVERGENCE ADJUSTMENT

1.ADJUST YOKE Z-AXIS FIRST TO GET EQUAL BLUE COLOR CIRCLES

2 .ADJUST BEAM BENDER 2 POLE MAGNET TO GET FOUR EQUAL COLOR CIRCLES

MAGNETS

RED

8.Referring to above, perform the following two steps:

a.Adjust the yoke Z-axis to obtain equal blue circles.

b.Adjust the appropriate beam bender tabs to obtain correct purity (four equal circles).

9.After correct purity is set, tighten the yoke clamp screw and remove the two screen magnets.

10.Remove the AC power and rotate the receiver 180 degrees (facing "magnetic south").

11.Reconnect the internal degaussing coil.

12.Turn the receiver on for 10 seconds (make sure the receiver came on) to perform internal degaussing, and then turn the receiver off.

13.Unplug the internal degaussing coil.

14.Turn the receiver on and check the purity by holding one (1) round magnet at the 3 o'clock and a second round magnet at 9 o'clock position. If purity is not satisfactory, repeat steps 8 through 14.

15.Turn off the receiver and reconnect the internal degaussing coil.

¯Convergence Adjustment

Caution: This procedure DOES NOT apply to bonded yoke and picture tube assemblies.

Do not use screen magnets during this adjustment procedure. Use of screen magnets will cause an incorrect display.

1.Remove AC power and disconnect the internal degaussing coil.

2.Apply AC Power and set the brightness to the Picture Reset condition. Set the Color control to minimum.

3.Make horizontal line.

4.Adjust the Red, Green and Blue Bias controls to get a dim white line.

RED

5.Restore the screen by removing the horizontal line.

6.Reconnect the internal degaussing coil and apply AC power.

7.Turn the receiver on for 10 seconds to perform internal degaussing and then turn the receiver off again.

8.Unplug the internal degaussing-coil.

9.Turn the receiver on, connect a signal generator to the VHF antenna terminal and apply a crosshatch signal.

Caution: During the convergence adjustment procedure, be very careful not to disturb the purity adjustment tabs. Purity should be confirmed before proceeding with the convergence adjustments.

Note: Make sure the focus is set correctly on this instrument before proceeding with the following adjustment.

10.Converge the red and blue vertical lines to the green vertical line at the center of the screen by performing the following steps (below TABLE).

a.Carefully rotate both tabs of the 4-pole ring magnet simultaneously in opposite directions from the 12 o'clock position to converge the red and blue vertical lines.

b.Carefully rotate both tabs of the 6-pole ring magnet simultaneously in opposite directions form the 12 o'clock position to converge the red and blue (now purple) vertical lines with the green vertical line.

11.Converge the red and blue horizontal with the green line at the center of the screen by performing the following steps. (below TABLE)

a.Carefully rotate both tabs of the 4-pole ring magnet simultaneously in the same direction (keep the spacing between the two tabs the same) to converge the red and blue horizontal lines.

b.Carefully rotate both tabs of the 6-pole ring magnet simultaneously in same direction (keep the spacing between the two tabs the same) to converge the red and blue (now purple) horizontal lines with the green horizontal line.

c.Secure the tabs previsouly adjusted by locking them in place with the locking tabs on the beam bender.

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