®. Color Bars
Color b a r pattern is composed of color bars in order of
luminance.
U p p e r p a t t e r n : F r o m left — White, yellow, cyan,
green, m a g e n t a , red, blue
a n d black
Lower p a t t e r n : F r o m left — Q, - I , * white and black
This signal is for chrominance (chroma) circuit adjustment.
•Refer t o p - 1 3 .
White
(75%)
Yellow
Cyan
Green Magenta
Red
Blue
Black
White (100%)
Black
Example
V C R Adjusting luminance and c h r o m a levels
Adjusting A u t o C o l o u r C o n t r o l (ACC)
Balancing c h r o m a level
Setting burst gate — phase and am
plitude
Measuring moire
TV receiver Adjusting c h r o m a circuit
Adjusting A C C circuit
T h e white level of upper color bars is 7 5 % in amplitude.
W h e n 100% white is required, use the white signal of the
lower pattern.
®. IQW Off
U p p e r bars can be displayed on full screen with this switch
depressed. When 100% white is required, turn the IQW on.
*IQ signal: In N T S C system, the color information is
broadcast o n I and Q signals. These signals are on the
orange-cyan and green-magenta axes respectively for ef
fective broadcasting. The axes have a 90° phase difference
each other. P A L system uses U a n d V axes. Ref. P I 3 .
Fig
2
Color Bar Pattern
Fig.
3
Color Bar Signal with
7 . 5 %
Setup
®. Chroma Off
T h e color bars can be m a d e colorless by depressing this
switch. This gray pattern is used t o adjust the linearity of
picture amplifier circuit, white balance, etc.
Upper -
pattern
- Lower pattern
Black level
Pedestal level
Fig. 4 Luminance Signal of Color Bar Pattern
17
Q
-S
Color
burst
White
Yellow
Cyan Green
Magenta
Red Blue
Black
Q
- I
W e i g h t e d : The amplitude is reduced to meet the sensitivity of
our eyes and t o avoid oversaturation.
H Sync
