SAMSUNG CK765DWT2X
Manual de Servicio

Alignment and Adjustments

4-3 Other Adjustments
4-3-1 General
1. Usually, a color TV needs only slight touchup adjustment upon installation. Check the basic characteristics such as height, horizontal and vertical sync and focus. 2. The picture should have good black and white details. There should be no objectionable color shading; if color shading is present, perform the purity and convergence adjustments described below. 3. Use the specified test equipment or its equivalent. 4. Correct impedance matching is essential. 5. Avoid overload. Excessive signal from a sweep generator might overload the front-end of the TV. When inserting signal markers, do not allow the marker generator to distort test results. 6. Connect the TV only to an AC power source with voltage and frequency as specified on the backcover nameplate. 7. Do not attempt to connect or disconnect any wires while the TV is turned on. Make sure that the power cord is disconnected before replacing any parts. 8. To protect against shock hazard, use an isolation transformer. If the chassis or parts of the cabinet become magnetized, poor color purity will result. If this happens, use an external degaussing coil. Slowly move the degaussing coil around the faceplate of the picture tube and the sides and front of the receiver. Slowly withdraw the coil to a distance of about 6 feet before removing power.

4-3-3 High Voltage Check
CAUTION: There is no high voltage adjustment on this chassis. The B+ power supply must be set to +130/155 volts. (Full color bar input and normal picture level). 1. Connect a digital voltmeter to the second anode of the picture tube. 2. Turn on the TV. Set the Brightness and Contrast controls to minimum (zero beam current). 3. The high voltage should not exceed 33KV. 4. Adjust the Brightness and contrast controls to both extremes. Ensure that the high voltage does not exceed 33KV under any conditions.

4-3-4 FOCUS Adjustment
1. Input a black and white signal. 2. Adjust the tuning control for the clearest picture. 3. Adjust the FOCUS control for well defined scanning lines in the center area of the screen.

4-3-2 Automatic Degaussing
A degaussing coil is mounted around the picture tube, so that external degaussing after moving the TV should be unnecessary. But the receiver must be properly degaussed upon installation. The degaussing coil operates for about 1 second after the power is switched ON. If the set has been moved or turned in a different direction, disconnect its AC power for at least 10 minutes.

4-3-5 Screen Adjustment
1. Turn to the ACTIVE channel. 2. Adjust the VR screen for a normal picture is (no blooming or flyback line).

3. Adjust the FOCUS control for well defined scanning lines in the center area of the screen. 4-6 Samsung Electronics