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:

CVBS out

Adjust with:

ZR203

ZR206

Required result:

Smallest possible

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:

CVBS out

Adjust with:

R14

Required result:

700mV

Correct:

0.1V5µS

100

90

10

0%

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:

CVBS out

Adjust with:

R4

Required result:

Correct:

 

 

%

 

 

VOLT

120

 

 

 

100

R

cy

0.7

 

80

g

MG

 

 

 

 

V

 

 

 

 

60

75

 

 

 

100

b

5

40

YL

 

 

U

0

 

 

 

20

yl

B

-5

 

 

 

0

20

G

mg

 

 

 

 

43

r

CY

0.3

 

 

Adjustments

Technical Manual LDK 20(S) - Studio Camera

4-37

Page 63
Image 63
Technicolor - Thomson LDK 20(S) technical manual Set-up, Black balance, Cvbs amplitude