No video picture, no sound.
Change C13,Q4,Q3
No video picture,
no sound.
Check if the reset circuit consisting
of C13, Q4, Q3,R11,R12,R13,R15,R16 is normal
(at a high level for tens of milliseconds,
then constantly at 0V).
Check whether there is
27MHz signal output.
Check if there is 128MHz
signal output on R49.
Check the loaded circuit
Crystal oscillator Y1 and
peripheral components
are defected or eroded.
Check whether
short-circuit or bad
solder on U3, U4
No
No
No
No
Yes
Yes
Yes
Yes
Yes
Reconnect the component in
short-circuit
Check U3.
27M waveform
SDRAM(R49 SDCLK) waveform
Check whether all the
voltages from the power
board to the decoder board
are normal.
CVBS(L27 point) waveform
Trouble shooting chart
Go
No
5-8
Содержание DVP3336/94
Страница 28: ...7 9 MAIN TOP PCB ...
Страница 29: ...7 10 MAIN BOTTOM PCB ...
Страница 30: ...7 11 LED DISPLAY TOP PCB ...
Страница 31: ...7 12 LED DISPLAY BOTTOM PCB ...
Страница 32: ...7 13 USB TOP PCB ...
Страница 33: ...7 14 USB BOTTOM PCB ...
Страница 34: ...7 15 LED TOP PCB ...
Страница 35: ...7 16 LED BOTTOM PCB ...
Страница 36: ...8 1 8 0 Exploded View Diagram ...