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HCD-GZR5D
27
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
demagnetizer. (Do not bring the head magnetizer close to the
erase head.)
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
supply voltage unless otherwise noted.
• Torque Measurement
Mode
Torque meter
Meter reading
FWD
CQ-102AS
2.0 – 8.0 mN • m
(20 to 80 g • cm)
(0.28 – 1.12 oz • inch)
FWD
back tension
CQ-102C
0.15 – 0.6 mN • m
(1.5 to 6 g • cm)
(0.021 – 0.083 oz • inch)
FF
CQ-201AS
5 – 17.7 mN • m
(50 to 177 g • cm)
(0.7 – 2.48 oz • inch)
REW
CQ-201B
5 –17.7 mN • m
(50 to 177 g • cm)
(0.7 – 2.48 oz • inch)
• Tape Tension Measurement
Mode
Torque meter
Meter reading
FWD
CQ-403A
more than 80 g
(more than 2.82 oz)
SECTION 6
ELECTRICAL ADJUSTMENTS
DECK SECTION
Tape
Signal
Used for
P-4-A063
6.3 kHz, – 10 dB
Azimuth Adjustment
0 dB = 0.775V
1. Demagnetize the record/playback head with a head
demagnetizer.
2. Do not use a magnetized screwdriver for the adjustments.
• Test Tape
RECORD/PLAYBACK HEAD AZIMUTH ADJUSTMENT
Procedure:
1. Mode: Playback
set
JACK board
PHONES jack
(J252)
+
–
level meter
test tape
P-4-A063
(6.3 kHz, -10 dB)
2. Turn the adjustment screw and check output peaks. If the peaks
do not match for L-CH and R-CH, turn the adjustment screw
so that outputs match within 1dB of peak.
Screw
position
L-CH
peak
within
1dB
Output
level
L-CH
peak
R-CH
peak
within
1dB
Screw
position
R-CH
peak
3. Mode: Playback
set
test tape
P-4-A063
(6.3 kHz, -10 dB)
oscilloscope
V
H
waveform of oscilloscope
in phase45
90
135
180
good
wrong
JACK board
PHONES jack
(J252)
4. After the adjustments, apply suitable locking compound to the
pats adjusted.
Summary of Contents for CDM74HF-DVBU101
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