Mechanical Adjustments; Electrical Adjustments; Tape Section - Sony WM-FX271 Service Manual

SECTION 3

MECHANICAL ADJUSTMENTS

PRECAUTION
1. Clean the following parts with a denatured-alcohol-moistened
swab :
playback head
capstan wheel assy
2. Demagnetize the 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 (2.5 V) unless otherwise noted.
Torque Measurement
Mode Torque meter
FWD CQ-102C
FWD
CQ-102C
Back Tension
FF, REW CQ-201B
pinch lever assy
rubber belt
Meter reading
20 – 42 g • cm
(0.28 – 0.58 oz • inch)
less than 2 g • cm
(less than 0.03 oz • inch)
more than 60 g • cm
(more than 0.83 oz • inch)

ELECTRICAL ADJUSTMENTS

• Supplied voltage : 2.5V
• Switch and control position
VOLUME control : maximum
AVLS switch : NORM
• Test Tape
Type
WS-48A 3 kHz, 0 dB

TAPE SECTION

Tape Speed Adjustment
Procedure:
test tape
WS-48A
(3 kHz, 0 dB)
set
1. Playback WS-48A (tape center part) in the FWD state and
adjust RV601 so that the frequency counter reading
becomes 3,000 Hz.
Specification Value:
Digital frequency counter
2,985 to 3,015 Hz
Adjustment Location:
– 7 –
SECTION 4
PRECAUTION
Signal Used for
tape speed adjustment
0 dB = 0.775 V
digital frequency
counter
0000
16 Ω
2 jack (J301)
RV601