Mechanical Adjustments; Electrical Adjustments Tape Section - Sony CFS-929SMK2 Service Manual

SECTION 4

MECHANICAL ADJUSTMENTS

PRECAUTION
1. Clean the following parts with a denatured alcohol-moistened
swab :
record/playback head
erase head
capstan
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: 12 V dc.
Torque Measurement DECK A
Mode Torque meter
Forward CQ-102C
Forward
CQ-102C
back tension
Fast Forward
and CQ-201B
Rewind
Tape Tension Measurement DECK A
Mode Tension meter
Forward CQ-403A
pinch roller
rubber belts
idlers
DECK B
Meter reading
2.21 to 5.39 mN • m
22.5 to 55 g • cm
(0.31 to 0.76 oz • inch)
0.20 to 0.49 mN • m
2 to 5 g • cm
(0.03 to 0.07 oz • inch)
5.89 to 11.76 mN • m
60 to 120 g • cm
(0.83 to 1.67 oz • inch)
DECK B
Meter reading
more than 150 g
(more than 5.29 oz)
SECTION 5
ELECTRICAL ADJUSTMENTS
TAPE SECTION 0 dB = 0.775 V
Standard Output Level
Output terminal SP OUT
load impedance
output signal level 0.775 V (0 dB)
Test Tape
Tape Signal
WS-48A 3 kHz, 0 dB
Tape Speed Adjustment DECK A
Procedure:
• Perform normal speed adjustment before high speed check.
Mode: playback (deck A)
record (deck B)
test tape
WS-48A
(3 kHz, 0 dB)
set
Adjust RV301 so that reading on digital frequency counter
becomes 3,000 Hz.
Specification Value:
Tape
Deck
speed
A Normal (playback)
A HI-SPEED DUBBING
(playback)
B HI-SPEED DUBBING
(record)
Frequency difference between the beginning and the end of the
tape should be within ± 1.0% (both Normal and Hi-speed).
Adjustment Location: – main board (component side) –
– MAIN board (component side) –
RV302
CFS-929SMK2
PHONES OUT
4 Ω 32 Ω
0.25 V (–10 dB)
Used for
tape speed adjustment
DECK B
digital frequency
counter
32 Ω
PHONES jack (J301)
Adjustment Frequency
point counter
RV302 3,000 to 3,030 Hz
(confirmation) 5,300 to 6,300 Hz
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