2 - 4
Alignment
Preparations
Alignment procedure
8.
White level
9.
Picture tube
type
10. PIP position
11. Screen
geometry
Screen
geometry
VGA
12. Picture
sharpness
13. Screen grid
voltage
U
SG
14. Adjustment of
the bridge coil
L53574
15. IF-Type
Feed in a grey scale test pattern with burst.
White balance:
Central position.
Contrast:
Maximum.
Colour contrast:
Mean value.
Screen brighness:
Mean value.
Call up the "White level alignment" menu via "Info-Cen-
ter" –> "Installation" –> "Dealer service menu" –> "8500" –>
"Picture settings".
Call up the "Picture tube type" menu via "Info-Center" –>
"Installation" –> "Dealer service menu" –> "8500" –> "Spe-
cial functions".
Feed in a transmitter picture.
Press and hold down the "PIP" button while switching on
with the mains switch.
Call up the "Screen geometry" menu via "Info-Center" –>
"Installation" –> "Dealer service menu" –> "8500".
Feed in a geometry test pattern.
Attention:
The "Horiz. Pos." alignment influences the
horizontal phase. Prior to carrying out this adjustment, set
the picture width to minimum and correct the lock-in position
if necessary using the "H-Shift" plug.
Reset:
The "Reset" field contains:
- either the optimum picture geometry data set at the
factory,
- or an average data record from the ROM if the set has
been started with the emergency data record.
After an incorrect alignment you may reload this basic data
at any time:
Call up the "Reset" menu via "Info-Center" –> "Installation"
–> "Dealer service menu" –> "8500" –> "Screen geometry".
Switch the set to channel position "AV4" and feed in a
geometry test pattern via the VGA socket.
Call up the "Reset" menu via "Info-Center" –> "Installation"
–> "Dealer service menu" –> "8500" –> "Screen geometry".
Feed in a convergence test pattern.
Contrast:
Maximum.
Set the brightness so that the black test pattern background
just brightens.
Feed in a black raster.
Adjust the picture screen brightness so the the grey area
just darkens.
Switch the unit to AV mode.
High-impedance voltmeter:
Test point R, G, B
(picture tube plate).
Determine the test point with the highest voltage level.
The bridge coil L53574 is adjusted during production and
should not be re-adjusted any more.
Call up the "Screen geometry" menu via "Info-Center" –>
"Installation" –> "Dealer service menu" –> "8500".
Set the picture width to minimum.
Oscilloscope channel 1: collector T53501.
Oscilloscope channel 2: cathode D53572.
Call up the "IF-Type" menu via "Info-Center" –> "Installation"
–> "Dealer service menu" –> "8500" –> "Special functions"
(to page 2) .
Adjust the values for
red, green
and
blue
so that the
picture becomes achromatic.
Set the picture type (T=Toshiba, P=Philips, V=Videocolor).
(This effects the peak beam current).
Adjust the vertical and horizontal PIP position so that the
small picture is not confined by the picture borders.
With the help of the user guide adjust the geometry values
first for the vertical deflection and then for the horizontal
deflection.
Only when this is done position the picture contents into the
centre of the screen. Re-adjust the picture width according
to the test pattern.
Saving:
The set value is saved by pressing the "yellow" button.
The picture geometry adjusts itself to the last saved value
when switching the TV set on again.
Check the geometry via the menu guide and correct it if
necessary.
Use the
FOC
control on the picture tube panel to adjust the
vertical lines about 5 cm to the right and left picture border
for minimum horizontal width.
Use the
SG
control (right control on the regulating section)
on the picture tube panel to adjust
170V
±
2.5V
.
Check for equal impulse width of the oscillograms and
correct if necessary using the coil
L53574
.
Re-adjust the picture width according to the test pattern.
Ajust to IF Type built into the set.
"National" (2950420221), "Multi 8" (2950426221),
"Multi 9", "Others".
