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SECTION 4
MECHANICAL ADJUSTMENTS
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/erase head with a head demag-
netizer.
3. Do not use a magnetized screwdriver for the adjustments.
4. After the head hight adjustments, apply suitable locking com-
4. After the head hight adjustments, apply suitable locking com-
pound to the parts adjusted.
5. The measurement and adjustments should be performed with the
rated power supply voltage unless otherwise noted.
Torque Measurement
Mode
Torque Meter
Meter Reading
Forward
CQ-102C
20 to 45 g • cm
(0.28 to 0.62 oz • inch)
Fast Forward
CQ-201B
80 to 200 g • cm
Rewind
(1.12 to 2.77 oz • inch)
Forward
CQ-102C
4 to 8 g • cm
Back Tension
(0.056 to 0.11 oz • inch)
Tape Tension Measurement
Mode
Tension Meter
Meter Reading
Forward
CQ-403A
100 to 170 g
(3.53 to 5.99 oz)
Forward Torque Adjustment
Torque meter
Meter reading
Procedure
Adjust the forward torque by
CQ-102C
20 to 45 g • cm
replace the spacer shown in
(0.28 to 0.62 oz• inch)
below chart.
Spacer
Part No.
t
3-307-493-01
0.1
3-307-493-11
0.15
3-307-493-21
0.2
3-307-493-31
0.25
Head Height Adjustment
Procedure :
1. Insert the mirror cassette (CQ-009C).
2. In playback mode and viewing from the front, adjust the head
1. Insert the mirror cassette (CQ-009C).
2. In playback mode and viewing from the front, adjust the head
heights to eliminate tape curl and tape twist at shown by arrows.
3. After the adjustments, apply suitable locking compound to
screws.
Part No.
t
3-578-138-01
0.1
3-578-138-11
0.2
nylon washer
(Taku-up side)
reflector
yoke plate
reel table magnet
tape
head
(rec / PB / erase)
Shim, head height
adjustment
adjustment
tape guide
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