HORIZONTAL ADJUSTMENTS

TM 11-5820-917-13

a. Remove the 6025 cover, module retaining bar, and the four screws securing

the 1A6 assembly to the mounting bracket.

b. Remove the plug to the 1A7 CRT display assembly, and then raise and set

aside the 1A 6 assembly.

Remove the four screws securing the 1A7 assembly to the mounting bracket.

Remove the 1A7 assembly and reconnect the plug to 1A7J1.

e. All of the adjustment points discussed in paragraphs 5-24 through 5-27 are

now accessible through holes in the CRT side cover.

NOTE

The CRT beam scans vertically. The yoke has been rotated 90-degrees

counterclockwise from the normal (NTSC) television positions. Horizontal

and vertical refer to the actual beam motion in this unit.

5-24. HORIZONTAL ADJUSTMENTS. There is some interaction between the hori-

zontal frequency, width, and linearity controls. The adjustment procedure should

be performed in the sequence indicated (see figure FO-18):

Apply video and synchronization signals to the CRT monitor.

b. Set the horizontal frequency control, R116, in the middle of the stable

region of the adjustment.

Adjust the horizontal width control, R124, for desired width.

Adjust the horizontal linearity control, R121, for best horizontal linearity.

Readjust the horizontal frequency control, R116, for stable picture.

Recheck width and linearity.

5-25. VERTICAL ADJUSTMENTS. Raster height is affected by a combination of

the low volt age supply, height coil L101 and the linearity sleeve located on the

neck of the CRT beneath the yoke. Adjust for vertical linearity as follows:

Apply video and synchronization signals to the monitor.

Adjust the width coil, L101, for desired height.

5-26. FOCUS ADJUSTMENT. The focus control, R107, provides an adjustment

for maintaining best overall display focus. However, because of the construction

of the gun assembly, in the CRT this control has only small effect on focus.

5-27. CENTERING. If the raster is not centered properly, it may be repositioned

by rotating the ring magnets behind the deflection yoke. The ring magnets should

not be used to offset the raster from its nominal center position because it would

degrade the resolution of the display. If the picture is tilted, rotate the entire

yoke.