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7
AMS Test Mode
• This mode is used for checking the AMS operations of the tape deck.
JIG
7-819-039-12 Alignment tape, AMS-110A
Procedure:
1. Press the
1
/
u
button to turn the unit ON.
2. Set the tape (AMS-110A).
3. Press the three buttons
p
, ENTER/NEXT , and DISC 3 button simultaneously.
4. “TEST MODE” is displayed on the fluorescent display tube.
5. Press the FUNCTION button and switch the function to the deck with the tape (AMS-110A).
6. Press the CD SYNC button. “AMS CHECK” is displayed on the fluorescent display tube and the tape is rewound.
7. AMS starts in the normal direction. If the AMS count is 2 at shut down, proceed to step 8.
“NG” is displayed at other times, and the deck stops.
8. AMS starts in the opposite direction. If the AMS count is 2 at shut down again, “OK” is displayed.
“NG” is displayed at other times.
Note: The
p
button of CD section will become effective and the aging of CD section will stop sometime, if the buttons described in step 3
are not pressed simultaneously. In that case, press
^
button and operate the CD section.
SELF-DIAGNOSIS
This model has the self-diagnosis function for the VIDEO and AUDIO decoder sections.
Immediately after the power on, the self-diagnosis function searches each operation of IC’s around the mechanism control microcomputer
(IC701).
The results can be checked by D502 of the VIDEO board.
Oscilloscope (Waveform)
Symptom
No error
MPEG decoder (IC506)
error
MPEG decoder (IC506)
or
DRAM (IC507) error
[VIDEO BOARD] (SIDE B)
H
L
Light
2 time blinking
H
L
H
L
3 time blinking
CN501
1
30
80
D502
SL501
SL502
SL503
CN502
51
IC505
31
(GND)
CT503
VIDEO
Frequency
Adjustment
Check point
(27 MHz)
50
100
81