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SECTION 4
MECHANICAL ADJUSTMENTS
SECTION 5
ELECTRICAL ADJUSTMENTS
1.
Demagnetize the record/playback head with a head
demagnetizer. (Do not bring the head demagnetizer close to
the erase head.)
2.
Do not use a magnetized screwdriver for the adjustments.
3.
After the adjustments, apply suitable locking compound to the
parts adjust.
4.
The adjustments should be performed with the rated power
supply 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
adjustment.)
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.
8.
Set to test mode. (Press key switch same time
GROOVE ENTER/NEXT and DISC 4 buttons.)
To exit from the test mode, press the
1/u
button.
•
Test Tape
PRECAUTION
1. Clean the following parts with a denatured-alcohol-moistened
swab:
record/playback head pinch roller
erase head
rubber belts
capstan
idlers
2. Demagnetize the record/playback head with a head
demagnetizer.
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
Forward
CQ-102C
36 to 61g•cm
(0.50 – 0.84 oz•inch)
Forward
CQ-102C
2 to 6g•cm
Back Tension
(0.026 – 0.082 oz•inch)
Reverse
CQ-102RC
36 to 61g•cm
(0.50 – 0.84 oz•inch)
Reverse
CQ-102RC
2 to 6g•cm
Back Tension
(0.026 – 0.082 oz•inch)
FF, REW
CQ-201B
61 to 143g•cm
(0.85 – 1.98 oz•inch)
Mode
Tension Meter
Meter Reading
Forward
CQ-403A
more than 100 g (3.53 oz)
Reverse
CQ-403R
more than 100 g (3.53 oz)
DECK SECTION
0 dB=0.775 V
Tape
Signal
Used for
P-4-A100
10 kHz, –10 dB
Azimuth Adjustment
WS-48B
3 kHz, 0 dB
Tape Speed Adjustment
P-4-L300
315 Hz, 0 dB
Level Adjustment
Record/Playback Head Azimuth Adjustment
• Tape Tension Measurement
DECK A
DECK B
Note:
Perform this adjustments for both decks.
Procedure:
1. Mode: Playback (FWD)
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 1 dB of peak.
set
MAIN board
CN207
pin
3
(L-CH)
pin
1
(R-CH)
MAIN board
CN207
pin
2
(GND)
+
–
level meter
test tape
P-4-A100
(10 kHz, –10 dB)
Screw
position
L-CH
peak
within
1 dB
output
level
L-CH
peak
R-CH
peak
within
1 dB
Screw
position
R-CH
peak
Содержание HCD-V3900
Страница 6: ... 6 This section is extracted from instruction manual ...
Страница 28: ...HCD V3900 V5900 35 36 6 7 SCHEMATIC DIAGRAM CD MOTOR SECTION See page 84 for IC Block Diagrams Page 47 ...
Страница 30: ...HCD V3900 V5900 39 40 6 9 SCHEMATIC DIAGRAM AUDIO SECTION See page 84 for IC Block Diagrams Page 49 Page 49 ...
Страница 42: ...HCD V3900 V5900 63 64 6 21 SCHEMATIC DIAGRAM VIDEO OUT SECTION See page 84 for IC Block Diagrams ...