Alignments - Philips 29PT5445/85 Service Manual

8. Alignments

Index of this chapter:
8.1 General Alignment Conditions
8.2 Hardware Alignments
8.3 Software Alignments and Settings
Note: The Service Default Alignment Mode (SDAM) is
described in the "Service Modes, Error Codes and Fault
Finding" section. SDAM menu navigation is performed by using
the MENU UP, MENU DOWN, MENU LEFT, and MENU
RIGHT keys of the remote control transmitter.
8.1 General Alignment Conditions
Perform all electrical adjustments under the following
conditions:
• AC voltage and frequency: according to country's
standard.
• Connect the television set to the AC power via an isolation
transformer.
• Allow the television set to warm up for approximately 20
minutes.
• Measure the voltages and waveforms in relation to chassis
ground (with the exception of the voltages on the primary
side of the power supply). Never use heatsinks as ground.
• Test probe: Ri > 10 M ohm; Ci < 2.5 pF.
• Use an isolated trimmer/screwdriver to perform the
alignments.
8.2 Hardware Alignments
7641
9527
A SDAM
7200
3606
1000 (TUNER)
ComPair
D
1003
Figure 8-1 Top view family board
8.2.1 Vg2 Adjustment
1. Activate SDAM by pressing the following key sequence on
the remote control transmitter: 0 6 2 5 9 6 directly followed
by the MENU button (do not allow the display to time out
between entries while keying the sequence).
2. Use the MENU UP/DOWN keys to highlight the WHITE
TONE sub menu.
0231
C
0212
5500
2503
5441
B
LOT
Focus
Screen
VG2
CL 36532044_036.eps
180603
Alignments L03.1U AA
3. Press the MENU LEFT/RIGHT key to enter the WHITE
TONE sub menu.
4. In the WHITE TONE sub menu, press the MENU UP/
DOWN keys to select NORMAL RED, NORMAL GREEN,
or NORMAL BLUE.
5. Use the MENU LEFT/RIGHT keys to set the values of
NORMAL RED, NORMAL GREEN and NORMAL BLUE to
'40'.
6. Press the MENU button twice to enter the normal user
menu.
7. In the normal user menu, use the MENU UP/DOWN keys
to highlight the PICTURE sub menu (if necessary).
8. Press the MENU LEFT/RIGHT keys to enter the PICTURE
sub menu.
9. Use the MENU UP/DOWN keys to select CONTRAST. Be
sure to record the current value of CONTRAST.
10. Use the MENU LEFT/RIGHT keys to set the value of
CONTRAST to '0'.
11. Use the MENU UP/DOWN keys to select BRIGHTNESS.
Be sure to record the current value of BRIGHTNESS.
12. Use the MENU LEFT/RIGHT keys to set the value of
BRIGHTNESS to minimum (OSD just visible in a dark
room).
13. Press the MENU button twice to return to the top level
SDAM menu.
14. Press the OSD/STATUS button to hide the SDAM
onscreen display ("S" indication remains visible). This, to
avoid interferences during the waveform measurements
15. Connect the RF output of a video pattern generator to the
antenna input, and input a 'black picture' test pattern to the
television set.
16. Set the oscilloscope to 50 V/div and the time base to 0.2
milliseconds (external triggering on the positive vertical
pulse with a 10:1 probe).
17. Ground the scope at the CRT panel and connect a 100:1
probe to one of the cathodes of the picture tube socket (pin
7= Red, pin 9= Green, and pin 3= Blue, see also schematic
diagram B1). Measure the level of the black current
measuring pulses. These are the second line (Red), third
line (Green), and fourth line (Blue) directly after the frame
blanking (see figure "V_cut-off").
Remark: This chassis is using a TDA93XX UOC series.
These use two different measuring pulses at each of the R,
G, and B outputs. The above-mentioned level applies to
the pulse with the lowest level of each gun.
18. Select the cathode with the highest V_dc value for the
alignment. Adjust the V_cut-off of this gun with the
SCREEN potentiometer (see figure "Top view family
board") on the LOT to the correct value (see table "Vg2
alignment values").
19. Press the OSD/STATUS button to display the SDAM
onscreen display.
20. Press the MENU button to enter the normal user menu.
21. In the normal user menu, use the MENU UP/DOWN keys
to highlight the PICTURE sub menu (if necessary).
22. Press the MENU LEFT/RIGHT keys to enter the PICTURE
sub menu.
23. Use the MENU UP/DOWN keys to select CONTRAST.
24. Use the MENU LEFT/RIGHT keys to reset the value of
CONTRAST to the original value.
25. Use the MENU UP/DOWN keys to select BRIGHTNESS.
26. Use the MENU LEFT/RIGHT keys to reset the value of
BRIGHTNESS to the original value.
27. Press the MENU button twice to return to the top level
SDAM menu.
28. Use the POWER button on the remote control transmitter
or the POWER button on the television set to turn off the
television set. This will save the changes made in SDAM.
8. EN 37