Grundig DAVIO 70 Service Manual page 28

Alignements / Alignment
Alignment
Brightness Maximum.
8. Horizontal Shift
Call up dialog line "Horizontal Width" via " " (DIALOG
CENTER) –> "OK" –> "SERVICE" –> "OK" –> Service Code
"8500" –> "GEOMETRY" –> "OK" and reduce the width of
the picture using button
Call up dialog line "Horizontal Shift".
9. Bridge Coil Bridge coil L53074 is adjusted in the factory and this setting
L53074 must not be changed.
Call up dialog line "Horizontal Width" via " " (DIALOG
CENTER) –> "OK" –> "SERVICE" –> "OK" –> Service Code
"8500" –> "GEOMETRY" –> "OK".
Set Horizontal Width to minimum.
Oscilloscope channel 1: collector T53001.
Oscilloscope channel 2: cathode D53072.
10. Focus - Feed in a convergency test pattern.
- Set the16:9 picture format (with 16:9 TV sets).
- Contrast to maximum.
- Set the screen brightness (
background of the test pattern just starts to brighten.
11. White Balance Feed in a grey scale test pattern with burst.
Contrast to maximum.
Colour contrast (
Screen brightness (
Call up dialog line "WHITE ADJUSTMENT" via " "
(DIALOG CENTER) –> "OK" –> "SERVICE" –> "OK" –>
Service Code "8500".
12. Screen Grid Call up dialog line "Cut-off align" via " " (DIALOG CENTER)
–> "OK" –> "SERVICE" –> "OK" –> Service Code "8500".
Voltage U
G2
Confirm with "OK".
2 - 4
Preparations
or .
v
) so that the black
i
) to mid-position.
v
) to mid-position.
Alignment Process
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.
Press button " " twice (GEOMETRY –> SERVICE) and
terminate the dialog line "End" with "with mem." –> "OK".
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.
0
With focus control on the picture tube panel, adjust
the vertical lines approx. 5cm from the right and left picture
edge to minimum horizontal width.
The sharpness in the middle must not seem to be worse
than the sharpness at the edges. If necessary, take an
average.
With button or set the values for "Green" or "Blue"
so that the picture becomes achromatic.
Check the white balance at minimum contrast and
maximum contrast.
Terminate the dialog line "End" with "with mem." –> "OK".
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 2033 F / 2035 F
GRUNDIG Service