8
BM-21/23
SECTION 3
ELECTRICAL ADJUSTMENTS
SECTION 2
MECHANICAL ADJUSTMENTS
Mode
Torque Meter
Meter Reading
FF
CQ-403A
more than 40 g
(more than 1.42 oz)
REW
CQ-403R
• Tape Pulling Force Measurement
PRECAUTION
1. Clean the following parts with a denatured-alcohol-moistened
swab :
playback head
rubber belts
capstan
idlers
pinch roller
2. Demagnetize the playback head with a head demagnetizer.
3. Do not use a magnetized screwdriver for the adjustments.
4. The adjustments should be performed with the rated power
supply voltage (3V) unless otherwise noted.
• Torque Measurement
Mode
Torque Meter
Meter Reading
FWD
CQ-102C
2.06 – 3.72 mN•m
(21 – 38 g•cm)
(0.30 – 0.52 oz•inch)
FWD
0.05 – 0.29 mN•m
Back Tension
(0.5 – 3 g•cm)
(0.01 – 0.04 oz•inch)
REV
CQ-102RC
2.06 – 3.72 mN•m
(21 – 38 g•cm)
(0.30 – 0.52 oz•inch)
REV
0.05 – 0.29 mN•m
Back Tension
(0.5 – 3 g•cm)
(0.01 – 0.04 oz•inch)
FF
CQ-201B
more than 60 g•cm
REW
(more than 0.84 oz•inch)
PRECAUTION
1. Power supply voltage : 3V
Test Tape
Tape Speed 4.8cm/s Adjustment
Switch position
TAPE SPEED Switch : 4.8 cm
Procedure:
1. Play back WS-48A (tape center portion) in FWD mode.
Adjust the RV601 so that the frequency counter reads 2,980
±
30 Hz.
2. Play back WS-48A (tape center portion) in REV mode.
Confirm that the reading of frequency counter is within 2.5 %
from the reading in step 1.
Type
Signal
Used for
WS-48A
3 kHz, 0 db
Tape Speed Adjustment
J102
set
EAR
18
Ω
test
WS-48A
(3 kHz, 0 dB)
frequency
counter
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