Philips DVP3850K/96/98 - No Video Picture, no Sound

4-10
No video picture, no sound.
Change CE1,Q1,Q2.
No video picture,
no sound.
Check if the reset circuit consisting
ofCE1,Q1,Q2 is normal (at a low
level for tens of milliseconds, then
constantl
y
at 3.3V
)
.
Check whether there is
27MHz si
g
nal out
p
ut.
Check the loaded circuit
Crystal oscillator Y1 and
peripheral components
are defected or eroded.
No
No
No
Yes
Yes
Yes
27Mhz waveform
Trouble shooting chart
Check whether all the voltages
from the power board to the
decoder board are normal.
CVBS(R884 point) waveform
Check if there is 135MHz
signal output on R193.
Check whether
short-circuit or bad
solder on U176,U186
SDRAM(R193 DCLK) waveform
Check U1.
No
No
Reconnect the component in
Yes
Yes
Check if short-circuit and
bad solder exist on Pin
72
Yes
No