@. Luminance Off
Luminance signal can be removed from the color bar sig
nal by depressing this switch. This chroma signal is used
to check the phase and amplitude variation of chroma sig
nal in t h e picture amplifier circuit.
(Q).
Chroma
C h r o m i n a n c e level of color bars a n d rasters is variable
within t h e range of ± 2 0 % .
R-Y (Modulated by E
R
-E
Y
)
C: Chrominance signal
'[Composed signal of (R-Y) + (B-Y)]
B - Y (Modulated by E
B
- E
Y
)
/ Time
T w o color subcarriers have been modulated by ( R - Y ) and ( B - Y )
signals respectively and then added before broadcasting.
Fig. 6 Enlarged Waveform of Chrominance Signal
(3.58 MHz)
Fig. 5 Chrominance Signal of Color Bar Pattern
E
B
- E
Y
= - 0 . 3 E
R
Fig. 7 Vector Diagram of Carrier Color Signal (Red)
A:Amplitude
Y:Luminance level
(b) Non
WEIGHTED
(C) WEIGHTED
Fig. 8 Phasor Diagrams of Color Bars (NTSC and PAL)
18
Amplitud
e
1/3.58 jus
90°
E
R
-E
Y
=0.7E
R
Red
Magenta
180°
Burst
Yellow
Green
Cyan
Blue
0°
90° (E
R
-E
Y
)
270°
/A:0.762 \
VY:0.3 /
113.2°
/ A : 0 . 8 3 4 \
V Y:0.41 /
45°
/ A : 0 . 9 0 \
VY:0.89/
173°
/A:0.834\
VY:0.59 '
225°
/ A : 0 . 7 6 2 \
\ Y : 0 . 7 /
293.2°
/ A:0.90\
V Y:0.11 /
353°
/A:0.63 \
V
Y:0.3 /
103.5°
Red
90° (E
R
-E
Y
)
Magenta
/ A:0.59 \
VY:0.41 /
61°
Q axis
(E
B
—E
Y
)
0°
/ A:0.45 \
V Y:0.89 /
167°
Yellow
180°
Burst
( A:0.59 )
\ Y i 0 . 5 9 /
241°
Green
Cyan
270°
/ A:0.63 \
\ Y:0.7 /
283.5°
—I axis
Blue
/ A:0.45 \
I Y:0.11 /
347°
