Alignment And Adjustments; Adjustment Conditions - Samsung CKF5607L Service Manual

6 Alignment and Adjustments

This section of the service manual explains how to make permanent adjustments to the monitor. Directions
are given for adjustments using the monitor Interface Board Ver. 2.0 and software (SoftJig).

6-1 Adjustment Conditions

Caution: Changes made without the SoftJig are saved only to the user mode settings. As such, the
settings are not permanently stored and may be inadvertently deleted by the user.
6-1-1 Before Making Adjustments
6-1-1 (a) ORIENTATION
When servicing, always face the monitor to the
east.
6-1-1 (b) MAGNETIC FIELDS
Whenever possible, use magnetic field isolation
equipment such as a Helmholtz field to surround
the monitor. If a Helmholtz field is not available,
frequently degauss the unit under test.
Caution: Other electrical equipment may cause
external magnetic fields which may
interfere with monitor performance.
Use an external degaussing coil to limit magnetic
build up on the monitor. If an external degaussing
coil is not available, use the internal degaussing
circuit. However, do not use the internal
degaussing circuit more than once per 30 minutes.
6-1-1 (c) WARM-UP TIME
The monitor must be on for 30 minutes before
starting alignment. Warm-up time is especially
critical in color temperature and white balance
adjustments.
6-1-1 (d) SIGNAL
Analog, 0.714 Vp-p positive at 75 ohm, internal
termination
Sync: Separate, Composite
(TTL level negative/positive)
6-1-1 (e) SCANNING FREQUENCY
Horizontal: 30 kHz to 70 kHz (Automatic)
Vertical: 50 Hz to 160 Hz (Automatic)
Unless otherwise specified, adjust at the 800 x 600
mode (53.6 kHz/85 Hz) signals.
Refer to Table 3-1 on page 3-3.
CKF5607L
6-1-1 (f) HIGH VOLTAGE ADJUSTMENT
Signal: 53.6 kHz/85Hz
Display image: crosshatch pattern
Contrast: Maximum
Brightness: Maximum
Limit: 25 kV ± 0.2 kV
Adjust VR501 to DC –204.0 V ± 0.5 V at EY14 and
GND.
Measure the hight voltage level at the anode cap.
High voltage should be within the limit as above.
If the high voltage needs adjustment use the
following procedure.
PROCEDURE
1. Turn the power off and disconnect the AC line
cord from the power source.
2. Unsolder and remove VR501 on the Main
PCB.
3. Replace VR501 and adjust the high voltage to
the specification.
4. Using a soldering iron, melt the adjustment
cap on VR501 to prevent any movement.
6-1-1 (g) G2 (SCREEN) VOLTAGE ADJUSTMENT
Signal: 53.6 kHz/85Hz
Display image: crosshatch pattern
Contrast: Maximum
Brightness: Maximum
Adjust the Screen VR of the FBT so that the G2
(Screen) Voltage for Toshiba CRT is 630 V ± 10 V.
6-1-1 (h) CENTER RASTER
Adjust SW401 so that the back raster comes to the
center when you apply a signal of 53.6 kHz/85Hz.
6-1