Samsung CK3366ZR4X/BWT Service Manual

4-3-3 High Voltage CheckCAUTION: There is no high voltage adjustment on this chassis.The B+ power supply must be set to +125 volts (Full color bar inputand normal picture level).1. Connect a digital voltmeter to the secondanode of the picture tube.2. Turn on the TV. Set the Brightness andContrast controls to minimum (zero beam cur-rent).3. The high voltage should not exceed 27.5KV.4. Adjust the Brightness and contrast controls toboth extremes. Ensure that the high voltagedoes not exceed 27.5KV under any conditions.4-3-4 FOCUS Adjustment1. Input a black and white signal.2. Adjust the tuning control for the clearest pic-ture.3. Adjust the FOCUS control for well definedscanning lines in the center area of the screen.4-3-5 Cathode Voltage Adjustment(Screen Adjustment)1. Connect CRT socket pin GK to an oscilloscopeprobe.2. Input a gray scale pattern. (Use a pattern gen-erator, PM5518)3. Use the P mode key (on the remote control)for the STANDARD picture.4. Adjust the Screen VR (on the FBT) so that thevoltage on the oscilloscope becomes 130+2.5V(See Fig. 4-1).4-3-6 Purity Adjustment1. Warm up the receiver for at least 20 minutes.2. Plug in the CRT deflection yoke and tightenthe clamp screw.3. Plug the convergence yoke into the CRT andset in as shown in Fig. 4-2.4. Input a black and white signal.5. Fully demagnetize the receive by applying anexternal degaussing coil.6. Turn the CONTRAST and BRIGHTNESS con-trols to maximum.7. Loosen the clamp screw holding the yoke.Slide the yoke backward or forward to pro-vide vertical green belt. (Fig. 4-3).8. Tighten the convergence yoke.9. Slowly move the deflection yoke forward,and adjust for the best overall green screen.10. Temporarily tighten the deflection yoke.11. Produce blue and red rasters by adjusting thelow-light controls. Check for good purity ineach field.12. Tighten the deflection yoke.Alignment and Adjustments4-16 Samsung ElectronicsFig. 4-1130 2.5V+_GND 14, 16" :120 2.5V20, 21" : 130 2.5V+_+__