– 20 –
SECTION 4
ADJUSTMENTS
4-1. MECHANICAL ADJUSTMENTS
TAPE RECORDER SECTION
PRECAUTION
1. Clean the following parts with a denatured-alcohol-moistened
swab :
record/playback/erase head pinch roller
rubber belts capstan
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
Torque Torque Meter Meter Reading
Forward CQ-102C
36 to 61 g • cm
(0.5 to 0.84 oz • inch)
Forward
CQ-102C
2 to 6 g • cm
Back Tension (0.028 to 0.083 oz • inch)
Reverse CQ-102RC
36 to 61 g • cm
(0.5 to 0.84 oz • inch)
Reverse
CQ-102RC
2 to 6 g • cm
Back Tension (0.028 to 0.083 oz • inch)
FF/REW CQ-201B
61 to 143 g • cm
(0.85 to 1.98 oz • inch)
Tape Tension Measurement
Mode Tension Meter Meter Reading
FWD CQ-403A
more than 100g
(more than 3.53 oz)
REV CQ-403A
more than 100g
(more than 3.53 oz)
4-2. ELECTRICAL ADJUSTMENTS
TAPE RECORDER SECTION 0dB = 0.775V
1. The adjustnemts should be performed in the order in the service
manual. (As a general rule playback circuit adjustment should
be completed beforeming recording circuit adjustment.)
2. The adjustments should be performed for bothe L-CH and R-
CH unless otherwise indicated.
Standard Intput Level
Input terminal LINE IN
source impedance 10kΩ
input signal level 0.5V (–3.8dB)
Standard Output Level
Output terminal LINE OUT
load impedance 47kΩ
output signal level 0.5V (–3.8dB)
Test Tape
Type Signal Used for
P-4-A100 10kHz, –10dB Azimuth Adjustment
WS-48B 3kHz, 0dB Tape Speed Adjustment
Record/Playback/Erase Head Azimuth Adjustment
Procedure :
1. Mode : FWD playback
2. Turn the adjustment screw for the maximum output levels. If
these levels do not match, turn the adjustment screw until both
of output levels match together within 1dB.
3. Phase Check
Mode : FWD playback
4. Change the reverse playback mode and repeat the step 1 to 3.
5. After the adjustment, lock the adjustment screw with suitable
locking compound.
Adjustment Location : – record/playback/erase head –
set
LINE OUT (JK301
47k
Ω
level meter
test tape
P-4-A100
(10kHz, –10dB)
L-CH
peak
R-CH
peak
L-CH
peak
R-CH
peak
Screw
position
output
level
within
1 dB
within
1 dB
screw positio
V
H
in phase
90
°
45
°
135
°
180
°
good
wrong
set
L-CH
R-CH
screen pattern
test tape
P-4-A100
(10kHz, –10dB)
Osilloscope
LINE OUT (JK301)
47k
Ω
47k
Ω
adjustment screw
FWD side REV side
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