Sony DTV-01, Руководство пользователя

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These simple matrixes are found in ICs frequently labeled as decoders or
are part of a processor. A video processor IC can contain an additional
simple electric matrix to convert the R-Y signals to their base Red signal
voltages by just adding the Y signal as (R-Y) + Y = R. The RGB signals
output can be used to drive the CRT.
R-Y resistor A R signal
Y resistor B
Identification
Component video is usually carried on three lines: Y, R-Y, & B-Y. They
can also abbreviated differently, but are the same:
·
Y, U, V
·
Y, Cr, Cb
·
Y, Pr, Pb
·
Y, R-Y, & B-Y.
The Y, Pr, Pb version designates the progressive instead of interlaced
picture scan format. This TV selects the DVD or HD component video
input from the TV/Video remote button. However, the HD signal must
have a horizontal frequency of 31 to 34kHz or the screen will remain dark
with just an “HD” OSD.
Waveforms
The following is a scope shot of component video signals that makes up a
blue screen picture. In the top waveform is the Y signal. It houses the
horizontal sync pulses (the vertical is not seen at this time base, but it is
present in the Y signal). The line between the sync pulses represents the
brightness level. The higher the line, the brighter the picture. Therefore,
a voltage at the sync pulse level is black.
The middle waveform is the B-Y signal. The area corresponding to the
horizontal sync pulse in the Y signal is at 0Vdc. The remainder of the
voltage minus the Y level is the Blue color level. Since this is a picture of
a blue screen, the voltage is high.
The bottom waveform is the R-Y signal. The area corresponding to the
horizontal sync pulse in the Y signal is also at 0Vdc. The red - Y level
during a blue screen is below 0Vdc. It will be equal to 0Vdc if the Y signal
is subtracted.
P M 3 3 9 4 , F L U K E & P H I L I P S
ch3
ch2
ch1
C H 1 ! 5 . 0 0 V ~
CH2!5.00 V~ L=121
C H 3 ! 5 . 0 0 V = C H P M T B 1 0 . 0 u s - 1 . 0 8 d v c h 1 p
1
2
3
B lu e s c r e e n – w a v e f o r m Y U V
N a m e L o c a t io n V o lt a g e / d iv
C h a n n e l 1 Y D V D o u t p u t 7 . 5 V p - p
C h a n n e l 2 B - Y D V D o u t p u t 5 V p - p
C h a n n e l 3 R - Y D V D o u t p u t 1 V p - p
T im e b a s e 1 0 u s e c / d iv
For comparison, the following component video waveforms are of a pic-
ture on a blue screen. The Y signal contains voltages of various bright-
ness levels centered on the screen between the H. sync pulses. The B-Y
and R-Y signals contain changing color levels in the middle of the screen.
Note that by looking at either color signal without the Y signal level, it is
not possible to know where the sync area is. It is therefore difficult for
your scope to sync on the R-Y or B-Y signal alone without a reference.
P M 3 3 9 4 , F L U K E & P H I L I P S
ch3
ch2
ch1
C H 1 ! 1 0 . 0 V ~
CH2!5.00 V~ L=121
C H 3 ! 5 . 0 0 V = C H P M T B 1 0 . 0 u s - 1 . 0 8 d v c h 1 p
1
2
3
P ic t u r e c e n t e r e d o n B lu e s c r e e n – w a v e f o r m Y s ig
N a m e L o c a t io n V o lt a g e / d iv
C h a n n e l 1 Y D V D o u t p u t 7 . 5 V p - p
C h a n n e l 2 B - Y D V D o u t p u t 5 V p - p
C h a n n e l 3 R - Y D V D o u t p u t 1 V p - p
T im e b a s e 1 0 u s e c / d iv