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— 13 —
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
2 to 6 g • cm
(0.02 - 0.08 oz • inch)
36 to 61 g • cm
(0.5 - 0.84 oz • inch)
Torque
Torque meter
FWD
FWD
back tension
REV
FF/REW
REV
back tension
FWD tension
REV tension
CQ-102C
CQ-102C
CQ-102RC
CQ-102RC
CQ-201B
CQ-403A
CQ-403R
2 to 6 g • cm
(0.02 - 0.08 oz • inch)
61 to 143 g • cm
(0.85 - 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
DECK SECTION
0 dB=0.775V
1. Demagnetize the record/playback head with a head damagnetizer.
2. Do not use a magnetized screwdriver for the adjustments.
3. After the adjustments, apply suitable locking compound to the
parts adjusted.
4. The adjustments should be performed with the rated power sup-
ply voltage unless otherwise noted.
5. The adjustments should be performed in the order given in this
service manual. (As a general rule, playback circuit adjustment
should be completed before performing recording circuit adjust-
ment.)
6. The adjustments should be performed for both L-CH and R-CH.
7. Switches and controls should be set as follows unless otherwise
specified.
Record/Playback Head Azimuth Adjustment
(Deck A, Deck B)
Note: Perform this adjustments for both decks.
Procedure:
1. Mode : Playback
set
test tape
P-4-A100
(10kHz, –10dB)
main board
CN403
Pin
3
(L-CH)
Pin
1
(R-CH)
level meter
Signal
Used for
Tape
Azimuth Adjustment
Tape Speed Adjustment
Level Adjustment
10 kHz, –10 dB
3 kHz, 0 dB
315 Hz, 0 dB
P-4-A100
WS-48B
P-4-L300
SECTION 5
MECHANICAL ADJUSTMENTS
Meter reading
36 to 61 g • cm
(0.5 - 0.84 oz • inch)
–
+
main board
CN403
Pin
2
(GND)