Sony KV-HF21M80 service manual Section SET-UP Adjustments, Beam Landing

KV-HF21M80

RM-952

SECTION 3

SET-UP ADJUSTMENTS

•	The following adjustments should be made when a complete	Perform the adjustments in the following order :
	realignment is required or a new picture tube is installed.	1.	Beam Landing
•	These adjustments should be performed with rated power	2.	Convergence
	supply voltage unless otherwise noted.	3.	Focus
		4.	White Balance

Controls and switches should be set as follows unless otherwise noted:		Note : Test Equipment Required.
PICTURE control	normal	1.	Color-bar/Pattern Generator
BRIGHTNESS control	normal	2.	Degausser
		3.	Oscilloscope

................................................................................................................................................................................................................................

Preparation :

•In order to reduce the influence of geomagnetism on the set's picture tube, face it east or west.

•Switch on the set's power and degauss with the degausser.

3-1. BEAM LANDING

1.	Input a white signal with the pattern generator.
	BrightnessContrast } normal
2.	Position neck assy as shown in Fig3-2.
3.	Set the pattern generator raster signal to a green raster.
4.	Move the deflection yoke to the rear and adjust with the purity
	control so that the green is at the center and the blue and the red
	take up equally sized areas on each side.
	(See Figures 3-1 through 3-3.)
5.	Move the deflection yoke forward and adjust so that the entire
	screen is green. (See Figure 3-1.)

Neck assy

DY

Note:

Neck Assy is exactly behind DY (no gap between Neck Assy and DY)

Fig. 3-2

Blue

Red

Green

6.	Switch the raster signal to blue, then to red and verify the
	condition.
7.	When the position of the deflection yoke has been decided,
	fasten the deflection yoke with the screws and DY spacers.
8.	If the beam does not land correctly in all the corners, use a
	magnet to adjust it.
	(See Figure 3-4.)

Fig. 3-3

Purity control corrects this area.

ba

cd

Disk magnets or rotatable disk magnets correct these areas (a-d).

Fig. 3-1

Deflection yoke positioning corrects these areas.

b

c

a

d

Fig. 3-4

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