Denon AVC-3000 - Page 36

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H
H
H
(2)
When
generate
internal
video
signal.
When
video
signal
is
not
supplied,
the
IC
internally
generate
the
video
signal
output.
SW1
is
ON
and
other
ones
are
OFF.
The
internal
video
signal
is
generated
by
frequency
dividing
X-tal
oscillator
XL1200,
7.15909
MHz
(color
subcarrier
x
2).
'\ ut Il | 1 11
a It 1 | Bell
Border
Signal
(VOB)
i!
a
7
|
1
|
i
I
I
tl
im)
1
.
Hite ttt it itt
Compound Signal (VOM)
Blue carrier signal
Color burst
Horizontal synchronous signal
Figure 3 Internal Video Timing
2.
SYNCHRONOUS
SIGNAL
DISCRIMINATION
&
SEPARATION
IC609
determines
whether
the
synchronous
signal
is
correct
or
not
and
separates
the
synchronous
signal.
When
the
synchronous
signal
input
to
pin
6
is
correct,
Pin
13
outputs
“High”,
if
not
correct
(no
video
signal
input
or
the
video
signal
includes
noise,
etc.),
Pin
13
outputs
"Low”.
When
the
"Low"
output
is
applied
to
microcomputer
(IC610),
IC608
(MB88323A-K1)
is
set
to
internal
video
blue
back.
When
the
video
signal
is
input
to
pin
6,
the
vertically
and
the
horizontally
synchrtonous
separated
signals
are
output
to
pin
10
and
pin
16
respectively.