Mechanical Adjustments - Sony Walkman WM-FX161 Service Manual

SECTION 4

MECHANICAL ADJUSTMENTS

PRECAUTION
1. Clean the following parts with a denatured-alcohol-moistened
swab:
playback head pinch roller
capstan rubber belt
2. Demagnetize the playback head with a head demagnetizer.
3. Do not use a magnetized screwdriver for the adjustments.
4. 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
Back Tension
FF, REW CQ-201B
• Tape Pulling Force Measurement:
Mode Tension Meter
FWD CQ-403A
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)
Meter Reading
more than 40 g
(more than 1.4oz)
– 7 –
SECTION 5
ELECTRICAL ADJUSTMENTS
PRECAUTION
• Supplied voltage : 2.5 V
• Switch and control position
VOL control : maximum
AVLS switch : NORM
NORM•DX CrO2/METAL•LOCAL switch :
NORM•ST CrO2/METAL•MONO switch : NORM•ST (E)
TAPE SECTION
Setup :
FM AM TAPE switch : TAPE
Test Tape
Tape Signal
WS-48A 3 kHz, 0 dB
0 dB = 0.775 V
Tape speed adjustment
Procedure :
test tape
WS-48A
Canadian: 32 Ω
(3 kHz, 0dB)
set
1. Play back WS-48A (tape center part) and Adjust the RV601 so
that the frequency counter reading becomes 3,000 Hz ± 15 Hz
2. Play back WS-48A tape the beginning and the end part.
Check that the frequency counter reading is within 1.5 % of
the reading of step 1.
NORM•DX (Canadian)
Used for
Tape Speed Adjustment
frequency
counter
E: 16 Ω
+
–
2
jack
RV601