SHARP 14U20
Manual de Servicio

PURITY CONVERGENCE ADJUSTMENT

No. Adjusment point Conditions/Adjusting procedure Waveform or others

PURITY ADJ. GREEN-ONLY Adjust 1 CONVERGENC 1. Receive the "Crosshatch Pattern" signal.

beam current to ~ 500 µA. ADJ. 2. Using the remote controller, call NORMAL mode. BGR

2. Maintain purity magnet at the zero magnetic ( To be done

a b B field and keep static convergence roughly after the purity STATIC CONVERGENCE
ours. through microscope. Adjust landing to the 2. Turn the 6-pole magnet to proper opening anA rank requirements. Fig. a

3. Observe points a, b, as shown Fig. 1-1 gle in order to superpose the blue and red col-

adjusted. adjustment.) 1. Turn the 4-pole magnet to a proper opening anG R

RGB 4. Orient raster rotation 0 eastward. gle in order to superpose the green colour over 5. Tighten up deflection coil screws. the blue and red colours.

Fig. 1-1

6. Make sure CRT corners landing meet the A DYNAMIC CONVERGENCE G

» Tightening torque: 108 20 N (11 ± 2 kgf) R

rank requirements. If not, stick magnet sheet 1. Adjust convergence on fringes of the B to correct it. screen in the following steps. A Note: This adjustment must be done after a) Fig. a: Drive the wedge at point "a" and swing
deflection coil upward. warming up the unit for 30 minutes or and swing the deflection coil downward. G

Fig. b

longer with a beam current over 500 µA. b) Fig. b: Drive the wedge at points "b" and "c" R G B B A = B the deflection coil rightward.
d) Fig. d: Drive the "b" wedge deeper and swing c) Fig. c: Drive the "c" wedge deeper and swing R

Fig. 1-2 the deflection coil leftward. Rank "A"
R

Fig. c 2. Fix all wedges on the CRT and apply glass tape over them. (On right of the CRT) BGR magnet unit (purity, 4-pole, 6-pole magnets) and B magnet unit lock screw. 3. Apply lacquer to the deflection yoke lock screw, G

7
A Finally received the Red-only and Blue-only sigB Wedge "a" A = B Fig. 1-3 Lacquer Rank "A" (On left of the CRT)

nals to make sure there is no other colours on the Fig. d screen.

About 100 Deg

Wedge "c" "b"

4-pole magnet 6-pole magnet CRT neck

(21") 20cm Lacquer

Purity magnet 40cm(14")

14U10/15 14U20/25

7-1 7-2