Adjustment; Mechanical Adjustment; Electrical Adjustment - Sony CFD-V77S Service Manual

5-1.

MECHANICAL ADJUSTMENT

PRECAUTION
1. Clean the following parts with a denatured-alchool-moistened
swab:
record/playback head
erase head
capstans
2. Demagnetize the record/playback head with a head
demagnetizer. (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.
Torque Measurement
Mode Torque Meter
FWD
CQ-102C
FWD
back tension
Fast Forward
CQ-201B
Rewind
Tape Tension Measurement
Torque Meter
CQ-403A
SECTION 5
ADJUSTMENTS
pinch roller
rubber belts
Meter Reading
18 – 60 g•cm
(0.25 – 0.83 oz•inch)
1.0 – 5.0 g•cm
(0.014 – 0.069 oz•inch)
45 – 95 g•cm
(0.62 – 1.32 oz•inch)
45 – 95 g•cm
(0.62 – 1.32 oz•inch)
Meter Reading
more than 60 g
(more than 2.12 oz)
— 10 —
5-2.

ELECTRICAL ADJUSTMENT

TAPE RECODER SECTION
Standard output level
Output
Load impedance
Output signal level
Test tape
Test Tape Signal
WS-48A 3 kHz, 0 dB
P-4-A063 6.3 kHz, –10 dB
Tape Speed Adjustment
Procedure :
Mode : Playback
test tape
WS-48A
(3kHz, 0dB)
set
Adjustment Value : normal tape speed
Adjust the tape speed adjustment control inside motor, so that the
frequency counter reading becomes 3,000 Hz.
Specification Value :
Digital frequency counter
2,910 – 3,090Hz
Frequency difference between the beginning and the end of the
tape should be within 1.5% (45 Hz).
Adjustment Location :
Tape speed adjustment
control inside motor
0dB = 0.775V
HP OUT
32 Ω
0.25 V (–10 dB)
Used for
Tape speed adjustment
Head azimuth adjustment.
digital frequency
counter
32 Ω
+
–
J301 (phones)