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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
–
AP-PAL-multi: 120 - 230 V
–
EU: 230 V
/ 50 Hz (± 10%).
AC
–
LATAM-NTSC: 120 - 230 V
–
US: 120 V
/ 60 Hz (± 10%).
AC
•
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 correct
ground (e.g. measure audio signals in relation to
AUDIO_GND).
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 menu", "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").
–
Press OK on the remote control before the cursor is
moved to the left.
–
In submenu "Option numbers" select "Store" and press
OK on the RC.
–
In main menu, select "Store" again and press OK 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.
or 230 V
/ 50 Hz (± 10%).
AC
AC
/ 50 Hz (± 10%).
AC
/ 50 Hz (± 10%).
AC
Alignments
BJ3.1A LA
Notes:
•
All changes must be stored manually.
•
If an empty NVM (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:
•
Press OK on the RC before the cursor is moved to the left.
•
In main menu select "Store" and press OK on the RC.
•
Press MENU on the RC to switch back to the main menu.
•
Switch the set back 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.
This chassis comes with two tuner types: the UV1318S for the
analogue sets and the TD1316AF for the hybrid sets. For the
digital tuner TD1316AF, no alignment is necessary, as the
AGC alignment is done automatically (standard value: "32"),
even during analogue reception. The analogue tuner UV1318S
however needs to be aligned as follows (use spectrum
analyser and RF generator):
•
Warm up set for a short period.
•
Tune set to 203.25 MHz.
•
Apply unmodulated carrier of 203.25 MHz (70 dBuV) to
antenna input.
•
Measure IF-output of the tuner (pin 11) with active probe
and spectrum analyser.
•
Adjust AGC (via SAM menu), until measured level is less
or equal to 103 dBuV (6-bit register, typical value is 42
dec).
•
Store settings and quit SAM.
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 is not necessary 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 a resistor of 1 kΩ
instead.
•
Connect AC voltmeter at 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.
EN 133
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