SHARP 14A1A
Service Manual

14A1-W/A/S,14AG1-M/S 14A2-A/S,14AG2-M/S

PURITY ADJUSTMENT
No. Adjusting point 1 PURITY ADJ. Adjusting procedure/conditions 1. Receive the GREEN-ONLY signal. Adjust the beam current to about 500 µA. 2. Degauss the CRT enough with the degausing coil. Note: Follow the Job Instruction Sheet to adjust the magnetic field. Vertical Bv : +0.030 mT (0.30 gauss) Horizontal Bh: +0.020 mT (0.20 gauss) (See page 12.) 3. Maintain the purity magnet at the zero magnetic field and keep the static convergence roughly adjusted. 4. Observe the points a, b as shown in Fig. 4-1 through the microscope. Adjust the landing to the rank A requirements. 5. Orient the raster rotation to 0 eastward. 6. Tighten up the deflection coil screws. » Tightening torque: 108 ± 20 N (11 ± 2 kgf) 7. Make sure the CRT corners landing meet the A rank requirements. If not, stick the magnet sheet to correct it. Note: This adjustment must be done after warming up the unit for 30 minutes or longer with a beam current over 500 µA. Note: Set the service mode by JA122 & JA124 (short) then press factory process R/C RGB key to change to RGB mono colour mode. * For the following colours press R/C RGB key to change. Waveform and others

a

b

Fig. 4-1

A

B A=B

Fig. 4-2 Rank "A" (on the right of the CRT)

A

Green-only

Blue-only

Red-only

B A=B

Signal-colour screen cleared

Fig. 4-3
Rank "A" (on the left of the CRT)

* Press R/C RGB key for 1 second in NORMAL MODE, the colour will change to RGB mono colour mode. The TEXT Key "R. G. Cy" Key can be directly use to change to other colours screen.

E 14