Inhaltsverzeichnis
Werbung
Alignement / Alignment
2. Picture Geometry
Measuring instruments: Colour video generator, dual-channel oscilloscope with 10:1 test probe.
Service works after replacement or repair:
Start with the vertical slope when adjusting the geometry!
- Horizontal and vertical deflection and replacement of the picture tube: alignment 2.1, 2.2
- Bridge coil L53074: Only necessary after unskillful manipulation of the horizontal deflection: alignment 2.3
Alignment
2.1 Vertical Slope
Call up the"Vertical Slope" menu via DIALOG CENTER –>
SERVICE –> Service Code "8500" –> "GEOMETRY"
2.2 Horizontal Shift
Max. brightness.
Call up dialog line "Horizontal Width" via DIALOG CENTER
–> SERVICE –> Service Code "8500" –> "GEOMETRY"
and reduce the width of the picture using button "
"+
".
Call up dialog line "Horizontal Shift".
2.3 Bridge Coil
Bridge coil L53074 is adjusted in the factory and this
L53074
setting must not be changed.
Call up dialog line "Horizontal Width" via DIALOG CENTER
–> SERVICE –> Service Code "8500" –> "GEOMETRY".
Set Horizontal Width to minimum.
Oscilloscope channel 1: collector T53001.
Oscilloscope channel 2: cathode D53072.
3. CRT Panel
Measuring instruments: High-resistance voltmeter, dual-channel oscilloscope with 10:1 test probe.
Service works after replacement or repair:
- CRT, CRT panel: alignment 3.1...3.3
Alignment
3.1 White Balance
Feed in a grey scale black/white test pattern with burst.
see 1.2
Contrast ( ) to maximum.
Colour contrast ( ) to mid-position.
Screen brightness ( ) to mid-position.
Call up dialog line "WHITE ADJUSTMENT" via DIALOG
CENTER –> SERVICE –> Service Code "8500".
3.2 Screen Grid
TV set in AV position.
Voltage U
Feed in a black raster.
G2
with TDA8375
Screen brightness: Grey raster just becoming dark.
Connect the voltmeter via 220kΩ to test points R, G and B.
Determine the point with the highest voltage level.
Voltmeter (220kΩ) or oscilloscope: test point with highest
voltage level.
3.3 Screen Grid
Call up dialog line "Cut-off align" via DIALOG CENTER –>
Voltage U
SERVICE –> Service Code "8500".
G2
with TDA8843
Confirm with "OK".
or
TDA8844
2 - 4
Preparations
-" or
Preparations
Alignment Process
Adjust the center line of the test pattern in the dialog line
"Vertical Slope" (typ. 30...33) with button "
so that it is just still visible.
Call up dialog line "End" via GEOMETRY –> " " –> SERVICE
and store "with mem.".
The picture geometry is adjusted to the value last stored
whenever the TV set is switched on.
Position the picture content in the middle of the raster using
button "
-" or "+
".
Re-adjust the horizontal width according to the test pattern.
With connector "ST-Shift" on the chassis (option), position
the test pattern in the middle of the screen.
Dependent on the scanning spread of the picture tube this
connector may be retrofitted, connected the other way
round, or the rating of the resistor may be changed.
Call up dialog line "End" via GEOMETRY –> " " –> SERVICE
and store "with mem.".
The picture geometry is adjusted to the value last stored
whenever the TV set is switched on.
Check the oscillograms for the same pulse width and re-
adjust it if necessary with coil L53074.
Adjust the horizontal width according to the test pattern.
Alignment Process
With button "
-" or "+
" set the values for "Green" or
"Blue" so that the picture becomes achromatic.
Terminate "with mem.".
Set the voltmeter to read 162.5V
control U
on the picture tube panel.
G2
Or adjust the oscilloscope as shown below.
162.5V±2.5V
105-110V
With adjustment control U
on the picture tube panel,
G2
adjust the line appearing first - red, green, blue or mixed-
colour - so that it is just well visible.
Return to the menu with "OK".
CUC 2030 F / 2031 F
-" or "+
"
±
2.5V with adjustment
Black level
GRUNDIG Service
Werbung
Inhaltsverzeichnis
