THOMSON STUDIO CAMERA LDK 20(S), Техническое руководство

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Adjustments Technical Manual LDK 20(S) - Studio Camera 4-37
Encoder Board PAL
Set-up
1. Switch off power. Place encoder board on service extender. Genlock camera with black burst signal. Switch
on power.
2. Connect oscilloscope via a vectorscope terminated with 75Ohm to the CVBS output of the camera.
3. Switch on colour bar.
Black balance
4. Turn chroma potentiometer R4 on encoder board fully clockwise (max. chroma).
5. Adjust the I and Q balance potentiometers for minimum unbalance in black.
Measure at: Adjust with: Required result:
CVBS out ZR203 Smallest possible
ZR206 dot in centre of
vectorscope
6. Turn chroma potentiometer R4 on encoder board fully counterclockwise (zero chrominance).
CVBS amplitude
7. Adjust the CVBS gain potentiometer to obtain an output amplitude of 700mV for Y.
Measure at: Adjust with: Required result: Correct:
CVBS out R14 700mV
0%
10
90
100
0.1V
5µS
VA+700mV
R-Y amplitude
8. Turn R-Y gain potentiometer ZR205 fully clockwise.
9. Connect MP7 on the encoder board to ground.
10. Adjust with the chroma potentiometer until the colour vector dots correspond with the indication marks on the
V-axis of the graticule.
Measure at: Adjust with: Required result: Correct:
CVBS out R4
20
40
R
60
80
0.7 100
120
20
43 0.3
g
YL
MG
cy
b
B yl
G
r
CY
mg
75
100
U
V
0
0
5
-5
% VOLT