Colour television Chassis
L6.2
AA 97.01
Adjustments on the 90° module panel
1.1 Horizontal amplitude; not adjustable; not present!
Introduction1.2 Vertical centring
In L6.2 TV sets a new 90° deflection module has beenIs adjusted with potentiometer R3921
1.3 Picture height
introduced for 21 " versions.Is adjusted with potentiometer R3903
1.4 East-west correction; not adjustable; not present!
Circuit description1.5 Horizontal centring (main PCB)
For the description of the audio- and video processing see theIs adjusted with potentiometer R3129 on the main PCB
description in the AA5 AA service manual.1.6 Focusing
The description of the power supply is present in the L6.1 AAIs adjusted with the focusing potentiometer in the line
service manual and for the description of the 110 ° moduleoutput transformer
see the service manual of the L6.2 AA chassis.1.7 AFC
a) Adjustment of the AFC and picture demodulator
General(all versions).
The differences between L6.1 and L6.2 with 90° module are:Select a non secam L/L' system in the SDAM mode
Black matrix picture tube for L6.2(negative modulation). Switch the tuner to HIGH
Stereo 2X 3 Watt/ stereo headphoneBAND (pin 1 1 of tuner 110 0 grounded). Connect a
Mono 3 Watt (also present in some L6.1 versions)pattern generator to pin 17 of the tuner via a
Loudspeakers 8 ohmscapacitor of 4.7nF and put a 82W resistor from the
Vertical shift 3 positionsoutput of the generator to ground. Connect a DC
Soft 3-4 knobsvoltmeter to pin 44 of IC7100. Adjust coil 5100 to
get 3V5 on pin 44 of IC7100.
Electrical consequences are a new defection module (90°), aThe signal of the generator has to be 38.9 MHz.
2X 3 Watt stereo amplifier panel and some small adaptationsb) Adjustment of the AFC and picture demodulator.
on the L6.2 main panel (derived from L6.1).(BAND 1 L. France versions only).
Same story as a) only the frequency of the
Differences in L6.2 90° module (compared with L6.2 110°generator has to be 33.9 Mhz with positive
module):modulation.
Key components:1.8 RFAGC
? CRT A51EAL155X47: service codeno. 48221311110 5If the picture of a strong local transmitter is reproduced
? LOT: service codeno. 482214010635distorted, adjust potentiometer R3130 until the picture
? Sops transformer: service codeno. 482214610896is undistorted.
PCB's:or: Connect a pattern generator (e.g. PM5518) to the
? 90° deflection module: service codeno. 4822 212 11533aerial input with RF signal amplitude = 1 mV.
Connect a multimeter (DC) at pin 5 of the tuner.
Remark:Adjust R3130 so that voltage at pin 5 of the tuner is
L6.2 110 ° modules are applied in 25" and 28" TV sets.8V5 +/- OV5 DC.
L6.2 90° modules are applied in 21" TV sets.
Adjustments on the CRT panel
90° deflection moduleVG2 cut-off points of picture tube
The electrical description of the 90° module is exactly theApply a black CVBS signal at the input pin 20 of scart. Adjust
same as for the 110 ° module except for the east/west modula-the brightness in order to have 1.6V during the line at the
tor which is not implemented. That means there is not anR,G.B outputs of the BIMOS pin 18,19.20 of IC7100. Put
east/west adjustment and there is not a horizontal amplitudepotentiometers R3326, R3316 and R3306 to the minimum
adjustment present.value (maximum voltage on the CRT cathodes). Adjust now
VG2 till the colour that luminates first is not visible anymore. |
ACEC
PHILIPS
