Pioneer AVIC-D3/XU/UC Service Manual page 192

1
Check 11: Is the video circuit OK?
<Outline> Composite signal and component signal are output from DVD-LSI (IC1501), and are output from the
A
HOST I/F (CN1901) via a buffer circuit.
IC1501
Composite
DVD_LSI
Component Y
Component Cb
Component Cr
Video
DAC
section
B
<Checking method> Playback DVD-REF-A1 TITLE2 CHAPTER5 (WHITE 100%), and monitor COMPO signal with
an oscilloscope with GNDV1 (stylus) being the reference. Set the trigger mode to "TV trigger" and
the trigger line to "150 line".
Check point 1 (stylus)
NO.
1 COMPO
C
In case of NG, check the applicable line, the periphery of the major components in the drawing above, soldering of the
peripheral components and defective components.
COMPO signal
D
<Video level readjustment method>
In case the video composite output is outside of the specification value, readjust the level according to the method
described below.
Turn the volume (VR1671) to adjust the video level within the range of 1.0 ± 0.02 Vpp.
The adjustment specification is 1.0 ± 0.02 Vpp.
IC1501
E
Y
LSI
Video
Cb
DAC
section
Cr
F
192
1
2
AVCC5
Video buffer circuit
NoMount
Fig 11.1: Video circuit
Specification value
1 000 mVpp ± 5 %
Color burst
Pedestal level
Horizontal sync signal
Fig 11.2: Waveform for the case of composite white 100% output
AVCC5
Q1701(NoMount)
Video buffer circuit
Q1702(NoMount)
Video buffer circuit
Q1704(NoMount)
Video buffer circuit
Fig 11.3: Video circuit (component)
2
3
COMPO
Reference waveform
Waveform 6
PEAK
Reference
Adjust this level within the
value
range of 1.0 ± 0.02 Vpp.
BOTTOM
AVIC-D3/XU/UC
3
CN1901
HOST I/F
CN1901
HOST I/F
Y
Cb
Cr
4
4