Aiwa TV-CN202, Service Manual, Page: 26 / 33

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1-4. Beam Center Convergence Adjustment
Make adjustments on the convergence with 4-pole and 6-pole magnets.
Operate each magnet in relation to the electron beam as shown in
Figs. 1-7 and 1-8. When performing this adjustment, verify whether
there is distortion in the focus adjustment. If necessary, carry out
adjustments again.
B G R
S N
N S
S
S
N N
B G R
Fig 1-7
G R B
N
N
N
S
S
S
S
N
N
S
G R B
S
N
Fig 1-8
In Fig. 1-7, two 4-pole magnets are stacked together so as to be of the
same polarity. Move the B and R beams to their respective direction,
by rotating the two 4-pole magnets together. By adjusting the opening
of the two magnets, it is possible to adjust the amount of the beam’s
movement.
In Fig. 1-8, the two 6-pole magnets are stacked together so as to be of
the same polarity. Move the B and R beams to their respective
direction, by rotating the two 6-pole magnets together. By adjusting
the opening of the two magnets, it is possible to adjust the amount of
the beam’s movement.
(1) Receive the dot pattern signal through the pattern generator.
(2) Pay attention to the center of the screen, and perform
adjustments with two 4-pole magnets so that the R beam and
the B beam perfectly align and become a magenta color. (refer
to Fig. 1-2)
(3) In the same way, pay attention to the screen, and perform
adjustments with a 6-pole magnet so that the magenta beam
and the G beam align and become a white dot. (refer to Fig.
1-3)
(4) After adjustments are completed, secure all magnets with the
lock link. (Refer to Fig. 1-4)
1-5. The Surrounding Convergence Adjustment
Make this adjustment after completion of adjustment 1-4.
(1) Shake the deflecting yoke up, down, right and left, and adjust
any discrepancies in the screen’s surroundings.
(2) Insert wedges in three locations in the gap between the
deflecting yoke and the surface of the CRT funnel in order to
secure the deflecting yoke. (refer to Fig. 1-9)
Position of wedge
Fig. 1-9
Wedge Wedge
Wedge