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– 14 –
1. Demagnetize the record/playback head with a head demagne-
tizer.
2. Do not use a magnetized screwdriver for the adjustments.
3. After the adjustments, apply suitable locking compound to the
parts adjust.
4. The adjustments should be performed with the rated power
supply voltage unless otherwise noted.
5. The adjustments should be performed in the order given in
this service manual. (As a general rule, playback circuit ad-
justment should be completed before performing recording
circuit adjustment.)
6. The adjustments should be performed for both L-CH and R-
CH.
7. Switches and controls should be set as follows unless other-
wise specified.
8. Set to the DOLBY NR OFF.
9. Set to the test mode.
(1) Press the
1
/
u
button to turn the power ON.
(2) Select the function “TAPE A or B”.
(3) Press the button of
p
,
[ENTER/NEXT]
, and
[DISC 3]
simultaneously, to set the tape deck test mode and blink
the indicator of disc tray number on the fluorescent indi-
cator tube.
(4) To exit from the test mode, press the
1
/
u
button.
• Test Tape
Record/Playback Head Azimuth Adjustment
Note:
Perform this adjustments for both decks
Procedure:
1. Mode: Playback
Tape
Signal
Used for
P-4-A100
10 kHz, –10 dB
Azimuth Adjustment
WS-48B
3 kHz, 0 dB
Tape Speed Adjustment
P-4-L300
315 Hz, 0 dB
Level Adjustment
31 to 71 g • cm
(0.43 – 0.98 oz • inch)
2 to 6 g • cm
(0.03 – 0.08 oz • inch)
31 to 71 g • cm
(0.43 – 0.98 oz • inch)
2 to 6 g • cm
(0.03 – 0.08 oz • inch)
71 to 143 g • cm
(0.99 – 1.99 oz • inch)
100 g or more
(3.53 oz or more)
100 g or more
(3.53 oz or more)
SECTION 6
ELECTRICAL ADJUSTMENTS
SECTION 5
MECHANICAL ADJUSTMENTS
Precaution
1. Clean the following parts with a denatured alcohol-moistened
swab:
record/playback heads
pinch rollers
erase head
rubber belts
capstan
idlers
2. Demagnetize the record/playback head with a head demagne-
tizer.
3. Do not use a magnetized screwdriver for the adjustments.
4. After the adjustments, apply suitable locking compound to the
parts adjusted.
5. The adjustments should be performed with the rated power sup-
ply voltage unless otherwise noted.
Torque Measurement
Mode
FWD
Torque meter
CQ-102C
Meter reading
FWD
back tension
REV
REV
back tension
FF/REW
FWD tension
REV tension
CQ-102C
CQ-102RC
CQ-102RC
CQ-201B
CQ-403A
CQ-403R
0 dB=0.775 V
DECK SECTION
DECK A DECK B
set
MAIN board
MD OUT jack (J101)
L-CH, R-CH
+
–
level meter
test tape
P-4-A100
(10 kHz, –10 dB)