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Abgleich / Alignment
GB
Alignment
All adjustment controls not mentioned in this description are adjusted during production and must not be re-adjusted in the case of repairs.
Measuring Instruments: Oscilloscope with 10:1 test probe, colour test pattern, high resistance voltmeter
Cecks and adjustments after replacement or repair of:
Power Supply: 1.
Horizontal Deflection: 2., 3.
Picture Tube, CRT-Panel: 2., 7.
IC150: 4., 5., 5a, 6.
Tuner: 5., 5a., 6.
Alignment
1. +A Voltage
Set luminance to mimimum.
Connect the voltmeter to the cathode of D682.
2. Screen grid
Feed in a grey scale test pattern.
voltage U
Adjust the screen brightness so that the gradation from the
SG
of the picture
darkest grey scale value to black is just still visible.
tube
Set the contrast ( ) to mid-value.
Measure test points R, G, B (on the CRT panel) to
determine the test point with the highest black level and
connect this point to the oscilloscope.
3. Line sharpness
Select the convergence test pattern.
Contrast ( ) to maximum.
Set the brightness so that the black background of the test
pattern is just brightening.
4. Vision demodulator
Feed in a standard test pattern at a low channel (Band 1).
French standard
Set the channel using the menu (do not use the Tuning
(vision carrier 33.4MHz)
System).
Vision demodulator
Feed in a standard test pattern at a channel as low as
(vision carrier 38.9 MHz)
possible (Band 3).
5. AFC reference
Tune in a local station with standardized channel spacing
alignment
(vision carrier 38.9 MHz) at a channel as low as possible
(Band 1) without fine tuning at the desired programme
position.
Call up the"AFC ALIGN" service menu (press and hold the
button ≥ 3 seconds while switching the TV on).
With
5a. Activation of AFC
–> OK –> –> –>
reference
6. Tuner AGC
Feed in a standard test pattern at a channel in the upper
range of the UHF band and store it at programme position 1.
RF ≥1.5mV (64dBµV, noise-free picture).
Switch the TV off with the power button.
Voltmeter: tuner contact 2.
Call up the Service Menu (press and hold the button " " for
≥ 3 seconds while switching the TV on).
With
7. White balance
Feed in a FuBK test pattern.
Set the colour contrast ( ) to minimum.
Set the contrast ( ) to maximum.
Adjust the screen brightness ( ) so that the gradation
from the darkest grey scale value to black is just still
visible.
3 - 2
Preparations
select the menu item "AFC ALIGN".
or
AFC "ON" / "OFF".
select the menu item "AGC ALIGN".
Alignment Process
With control R654 set the voltage to
112V (14" Orion), 105V (14" Philips), 124V (15...21").
With the control SG adjust the black level at the test point
with the highest black level to approx. 100V...105V for 14"
picture tubes and 150V...155V for 15...21" picture tubes.
Schwarzwert
Black level
100V...100V 14";
105-110V
150V...155V 15...21"
With the focus control U
on the focusing panel adjust the
F
horizontal lines for maximum sharpness.
With trimmer C136 set the DC level at IC150-(9) to 4V.
With filter F130 set the DC level at IC150-(9) to 4V. Check
the AFC reference.
The button
or
activates the automatic AFC alignment
function. The AFC average value is stored in IC 830.
On activation of AFC Reference a rectified IF-voltage is
measured at the AFC output of the IC150-(9) which is
used on station search as a comparative value for VCR-
RF playback (station identification "AV") to readjust the
modulator drift.
With the
and buttons tune the station so that noise just
starts to appear in the picture. Then reduce the value so
that the noise just disappears from the picture.
Terminate with " ".
or:
With the button
or
set the voltage to 3.3V
Set the controls VG and VB on the CRT panel so that no
discolouration is visible in the grey scale.
CUC 7301
±
0.4V.
GRUNDIG Service
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