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Colour television
Introduction
In L6.2 TV sets a new 90° deflection module has been
introduced for 2 1 " versions.
Circuit description
For the description of the audio- and video processing see the
description in the AA5 AA service manual.
The description of the power supply is present in the L6.1 AA
service manual and for the description of the 1 1 0 ° module
see the service manual of the L6.2 AA chassis.
General
The differences between L6.1 and L6.2 with 90° module are:
Black matrix picture tube for L6.2
Stereo 2 X 3 Watt/ stereo headphone
Mono 3 Watt (also present in some L6.1 versions)
Loudspeakers 8 ohms
Vertical shift 3 positions
Soft 3-4 knobs
Electrical consequences are a new defection module (90°), a
2 X 3 Watt stereo amplifier panel and some small adaptations
on the L6.2 main panel (derived from L6.1).
Differences in L6.2 90° module (compared with L6.2 1 1 0 °
module):
Key components:
• CRT A51EAL155X47: service codeno. 4 8 2 2 1 3 1 1 1 1 0 5
•
LOT:
service codeno. 4 8 2 2 1 4 0 1 0 6 3 5
•
Sops transformer:
service codeno. 482214610896
PCB's:
• 90° deflection module: service codeno. 4822 212 11533
Remark:
L6.2 1 1 0 ° modules are applied in 25" and 28" TV sets.
L6.2 90° modules are applied in 2 1 " TV sets.
90° deflection module
The electrical description of the 90° module is exactly the
same as for the 1 1 0 ° module except for the east/west modula-
tor which is not implemented. That means there is not an
east/west adjustment and there is not a horizontal amplitude
adjustment present.
Adjustments on the 90° module panel
1 . 1
Horizontal amplitude; not adjustable; not present!
1 . 2
Vertical centring
Is adjusted with potentiometer R3921
1 . 3
Picture height
Is adjusted with potentiometer R3903
1.4
East-west correction; not adjustable; not present!
1.5
Horizontal centring (main PCB)
Is adjusted with potentiometer R3129 on the main PCB
1 . 6
Focusing
Is adjusted with the focusing potentiometer in the line
output transformer
1.7
AFC
a) Adjustment of the AFC and picture demodulator
(all versions).
Select a non secam L/L' system in the SDAM mode
(negative modulation). Switch the tuner to HIGH
BAND (pin 1 1 of tuner 1 1 0 0 grounded). Connect a
pattern generator to pin 1 7 of the tuner via a
capacitor of 4.7nF and put a 82W resistor from the
output of the generator to ground. Connect a DC
voltmeter to pin 44 of IC7100. Adjust coil 5100 to
get 3V5 on pin 44 of IC7100.
The signal of the generator has to be 38.9 MHz.
b) Adjustment of the AFC and picture demodulator.
(BAND 1 L. France versions only).
Same story as a) only the frequency of the
generator has to be 33.9 Mhz with positive
modulation.
1.8
RFAGC
If the picture of a strong local transmitter is reproduced
distorted, adjust potentiometer R3130 until the picture
is undistorted.
or: Connect a pattern generator (e.g. PM5518) to the
aerial input with RF signal amplitude = 1 mV.
Connect a multimeter (DC) at pin 5 of the tuner.
Adjust R3130 so that voltage at pin 5 of the tuner is
8V5 +/- OV5 DC.
Adjustments on the CRT panel
VG2 cut-off points of picture tube
Apply a black CVBS signal at the input pin 20 of scart. Adjust
the brightness in order to have 1.6V during the line at the
R,G.B outputs of the BIMOS pin 1 8 , 1 9 . 2 0 of IC7100. Put
potentiometers R3326, R3316 and R3306 to the minimum
value (maximum voltage on the CRT cathodes). Adjust now
VG2 till the colour that luminates first is not visible anymore.
Chassis
L6.2
AA
97.01
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