Pioneer PDP-5016, Руководство по обслуживанию

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3-4. COF Damage
(1) In case of shorting or opening the IC output of COF, it may
show one or several vertical lines.
O
Test Point: Enlarge the after measuring output TP of
COF~GND.
O
Wave format: As shown Output of (Fig. 7)
In case of normal wave output, when STB signal is
generated, maintain High output. And when STB signal
is generated again must be fall Low.
But when IC of COF is poor, STB signal is not generated
Output falls with Low.
(2) In case of being damage IC of COF or power resistance,
the screen doesn’t be shown or happens discharge partially.
O
Test Point: Enlarge the after measuring output TP of
COF~GND
O
Wave format: Output wave doesn’t come out
O
Measurance position: Enlarge the after measuring output
TP of COF (Full White Pattern)
3-5. Crystal(CTRL B/D: X2) damage
(1) When Crystal is damage, the screen doesn’t be shown.
O
Test Point: Measuring 3pin of GND~Crystal(Ctrl B/D: X2)
O
Wave format: Output wave doesn’t come out
(2) In case of unusual launch of the Crystal, it may blink the
screen.
O
Wave format: As shown (Fig. 8)
O
Measurance position: Measuring 3pin of Crystal(X2:
100MHz) (Full White Pattern)
(Fig. 7) When IC output of COF is poor
<COF Normal Output Wave >
(Fig. 8) When Crystal is poor
<Crystal Normal Output Wave >
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