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– 12 –
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 demagne-
tizer. (Do not bring the head demagnetizer 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.
6. Power supply voltage: 9 V dc.
Torque Measurement DECK A DECK B
Mode
Torque meter
Meter reading
Forward
CQ-102C
22.5 to 55 g • cm
(0.31 to 0.76 oz • inch)
Forward
CQ-102C
2 to 5 g • cm
back tension
(0.03 to 0.07 oz • inch)
Fast Forward
60 to 120 g • cm
and
CQ-201B
(0.83 to 1.67 oz • inch)
Rewind
Tape Tension Measurement DECK A DECK B
Mode
Tension meter
Meter reading
Forward
CQ-403A
more than 150 g
(more than 5.29 oz)
SECTION 4
ELECTRICAL ADJUSTMENTS
SECTION 3
MECHANICAL ADJUSTMENTS
TAPE SECTION 0 dB = 0.775 V
Standard Output Level
Output terminal
SP OUT
PHONES OUT
load impedance
6
Ω
32
Ω
output signal level
0.775 V (0 dB)
0.25 V (–10 dB)
Test Tape
Tape
Signal
Used for
WS-48A
3 kHz, 0 dB
tape speed adjustment
Tape Speed Adjustment DECK A DECK B
Procedure:
• Perform normal speed adjustment before high speed check.
Mode: playback (deck A)
record (deck B)
Deck
Tape
Adjustment
Frequency
speed
point
counter
A
Normal (playback)
RV301
2,985 to 3,015 Hz
A
HI-SPEED DUBBING
(confirmation) 5,700 to 6,500 Hz
(playback)
B
HI-SPEED DUBBING
———
———
(record)
Frequency difference between the beginning and the end of the
tape should be within ± 1.5% (both Normal and Hi-speed).
Adjustment Location: – main board (component side) –
0000
PHONES jack (J301)
digital frequency
counter
set
32
Ω
test tape
WS-48A
(3 kHz, 0 dB)
RV301
Adjust RV301 so that reading on digital frequency counter
becomes 3,000 Hz.
Specification Value: