JVC AV-20N3/D, AV-20NMG3/-A Purity / Convergence Adjustment, Purity Adjustment, # P/C Magnets

AV-20N3

AV-20NMG3

AV-20NMG3B

PURITY / CONVERGENCE ADJUSTMENT

PURITY ADJUSTMENT

1.	Demagnetize CRT with the demagnetizer.
2.	Loosen the retainer screw of the deflection yoke.
3.	Remove the wedges.
4.	Input a green raster signal from the signal generator, and turn
	the screen to green raster.

W EDGE

CR T

DEFLECTION

YOKE

P

4 6

P / C

5.	Move the deflection yoke backward.
6.	Bring the long lug of the purity magnets on the short lug and
	position them horizontally. (Fig.2)
7.	Adjust the gap between two lugs so that the GREEN RASTER
	will come into the center of the screen. (Fig.3)
8.	Move the deflection yoke forward, and fix the position of the
	deflection yoke so that the whole screen will become green.
9.	Insert the wedge to the top side of the deflection yoke so that it
	will not move.
10.	Input a crosshatch signal.
11.	Verify that the screen is horizontal.
12.	Input red and blue raster signals, and make sure that purity is
	properly adjusted.

MAGNETS

#P/C MAGNETS

P : PURITY MAGNET

4 : 4 POLES (convergence magnets)

6 : 6 POLES (convergence magnets)

Fig.1

PURITY MAGNETS

Long lug

Short lug

Bring the long lug over the short lug and position them horizontally.

Fig.2

(FRONT VIEW ) GREEN RASTER

CEN TER

Fig.3

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