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— 4 —
NOTES ON HANDLING THE OPTICAL PICK-UP BLOCK
OR BASE UNIT
The laser diode in the optical pick-up block may suffer electrostatic
break-down because of the potential difference generated by the
charged electrostatic load, etc. on clothing and the human body.
During repair, pay attention to electrostatic break-down and also use
the procedure in the printed matter which is included in the repain
parts.
The flexible board is easily damaged and should be handled with
care.
NOTES ON LASER DIODE EMISSION CHECK
The laser beam on this model is concentrated so as to be focused on
the disc reflective surface by the objective lens in the optical pick-up
block. Therefore, when checking the laser diode emission, observe
from more than 30 cm away from the objective lens.
LASER DIODE AND FOCUS SEARCH OPERATION CHECK
Carry out the “S curve check” in “CD section adjustment” and check
that the S curve waveform is output three times.
SECTION 1
SERVICING NOTE
FL Display Tube, LED All Lit and Key Check mode
When the TUNER/BAND , DISPLAY/DEMO , and FILE 2 but-
tons are pressed simultaneously, the FL display tube and LEDs will
all light up. Press any button to enter the key check mode.
When the key check mode is entered, the FL display tube displays
“K 1 J0 V0”. Each time a button is pressed, the counter increases in
the following order, K 2
n
K 3
n
K 4.
If buttons already pressed once are pressed again, the counter will
not increase. When the VOLUME knob is rotated in the + direction,
the count increases in the following order.
V1
n
V2
n
V3.
When rotated in the – direction, it decreases in the following order.
V0
n
V9
n
V8.
When the AMS dial is rotated in the clockwise direction, the count
increases in the following order.
J1
n
J2
n
J3.
When rotated in the counterclockwise direction, it decreases in the
following order.
J0
n
J9
n
J8.
To exit form the test mode, press the TUNER/BAND , DISPLAY/
DEMO , FILE 2 buttons simultaneously again.
Switching the channel step 9 kHz/10 kHz
Press ENTER/NEXT button and SYSTEM POWER button simul-
taneously to switch the AM channel step 9 kHz and 10 kHz. Be sure
not to change with carelessness.
All Reset
When TUNER/BAND , DISPLAY/DEMO , and FILE3 buttons
are pressed simultaneously, the contents of a preset are restored to
those at shipping.
SECTION 2
GENERAL
This section is extracted from
instruction manual.
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