Philips BJ3.0E, Руководство по обслуживанию

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Alignments EN 135 BJ3.0E PA 8.
8. Alignments
Index of this chapter:
8.1 General Alignment Conditions
8.2 Hardware Alignments
8.3 Software Alignments
8.4 Option Settings
Note: The Service Default Mode (SDM) and Service Alignment
Mode (SAM) are described in chapter 5. Menu navigation is
done with the CURSOR UP, DOWN, LEFT or RIGHT keys of
the remote control transmitter.
8.1 General Alignment Conditions
Perform all electrical adjustments under the following
conditions:
•
Power supply voltage (depends on region):
–
AP-NTSC: 120 V
AC
or 230 V
AC
/ 50 Hz (
±
10%).
– AP-PAL-multi: 120 - 230 V
AC
/ 50 Hz (
±
10%).
– EU: 230 V
AC
/ 50 Hz (
±
10%).
– LATAM-NTSC: 120 - 230 V
AC
/ 50 Hz (
±
10%).
– US: 120 V
AC
/ 60 Hz (
±
10%).
• Connect the set to the mains via an isolation transformer
with low internal resistance.
• Allow the set to warm up for approximately 15 minutes.
• Measure voltages and waveforms in relation to chassis
ground (with the exception of the voltages on the primary
side of the power supply).
Caution: It is not allowed to use heatsinks as ground.
• Test probe: Ri > 10 Mohm, Ci < 20 pF.
• Use an isolated trimmer/screwdriver to perform
alignments.
8.1.1 Initial Settings
Press the “Menu” button on the RC. Select “TV settings” and
then “Picture”. Change the following initial setting in order to
perform all electrical adjustments:
1.
Set “Active Control” to “Off”.
2. Set “Light sensor” to “Off”.
8.1.2 Alignment Sequence
• First, set the correct options:
–
In SAM, select “Options”, and then “Option numbers”.
– Fill in the option settings for “Group 1” and “Group 2”
according to the set sticker (see also paragraph
"Option Settings").
– Store the OPTIONS by pressing OK on the remote
control
before the cursor is moved to the left.
– Press STORE on the RC.
– Switch the set to STAND-BY.
• Warming up (>15 minutes).
• White-D alignment.
8.2 Hardware Alignments
Not applicable.
8.3 Software Alignments
Put the set in SAM mode (see Chapter 5 "Service Modes, Error
Codes and Fault Finding"). The SAM menu will now appear on
the screen. Select ALIGNMENTS and go to one of the sub
menus. The alignments are explained below.
Notes:
• All changes must be stored manually.
• If an empty EAROM (permanent memory) is detected, all
settings are set to pre-programmed default values.
With the software alignments of the Service Alignment Mode
(SAM), “Tuner AGC”, “Tuner IF PLL Offset” and the
“Whitepoint” settings can be aligned.
To store the data: Use the RC button OK before the cursor is
moved to the left, press STORE on the RC, press MENU to
switch to the main menu and then switch to STAND-BY mode.
For the next alignments, supply the following test signals via a
video generator to the RF input:
•
EU/AP-PAL models: a PAL B/G TV-signal with a signal
strength of at least 1 mV and a frequency of 475.25 MHz
• US/AP-NTSC models: an NTSC M/N TV-signal with a
signal strength of at least 1 mV and a frequency of 61.25
MHz (channel 3).
• LATAM models: an NTSC M TV-signal with a signal
strength of at least 1 mV and a frequency of 61.25 MHz
(channel 3).
8.3.1 Tuner AGC
Purpose: To keep the tuner output signal constant as the input
signal amplitude varies.
For this chassis, no alignment is necessary, as the AGC
alignment is done automatically (standard value: “32”).
8.3.2 IF PLL Offset
The IF PLL Offset value needs to be realigned in case the MPIF
and/or the NVM have been replaced. This value needs NOT be
realigned in case only the tuner has been replaced.
Default values are:
•
For PAL B/G: 40
• For SECAM L: 32
In case the result is not satisfying (distortion in sound and/or
discolouration in left and right part of the picture), use the
following method to align the IF PLL Offset value:
•
Switch set “off”.
• Disconnect speakers and connect resistor of 1k
Ω
instead.
• Connect AC voltmeter over resistor.
• Switch set “on”.
• Put “Volume” at maximum.
• Align PLL until voltage is at minimum.
In case the minimum value on the AC voltmeter is found in a
range of IF PLL Offset values, the value should be taken that is
in the middle of this range.
8.3.3 White Point
• Set “Active control” to “Off” as earlier described.
• Choose “TV menu”, “TV Settings” and then “Picture” and
put:
–
“Dynamic contrast” to “Off”.
– “Colour enhancement” to “Off”.
– “Light sensor” to “Off”.
– “Clear LCD” to “On” where applicable.
– “Colour” to "0".
– “Contrast” to "100".
• Go to the SAM and select “Alignments”-> “Whitepoint”.
White point alignment:
• Use a 100% white screen as input signal and set the
following values: