Pioneer AVH-P5950DVD/XN/RC Service Manual page 52

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
HOST I/F (CN1901) via a buffer circuit.
A
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
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.(Note : Units are exchanged, the video output is not adjusted. )
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
Y
E
LSI
Video
Cb
DAC
section
Cr
F
52
1
2
AVCC5
Video buffer circuit
NoMount
Fig 11.1: Video circuit
an oscilloscope with GNDV1 (stylus) being the reference. Set the trigger mode to "TV trigger" and
the trigger line to "150 line".
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)
AVH-P5950DVD/XN/RC
2
3
COMPO
Reference waveform
Waveform 6
PEAK
Reference
Adjust this level within the
value
range of 1.0 ± 0.02 Vpp.
BOTTOM
Y
Cb
Cr
3
4
CN1901
HOST I/F
CN1901
HOST I/F
4