Aiwa TV-AS215 Service Manual page 11

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.
S N
B G R
N S
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.
N
S S
B G R
N N
S
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 from 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 B beam are
perfectly aligned 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 G
beam are aligned 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)
S
B G R
N
S
Fig 1-7
S N
B G R
S
N
S
N
Fig 1-8
1-5. The Surrounding Convergence Adjustment
Perform this adjustment after completion of adjustment 1-4.
(1) Shake the deflecting yoke up, down to the 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)
N
– 11 –
Wedge
Wedge
Wedge
Position of wedge
Fig. 1-9
Wedge