Mechanical Adjustments; Electrical Adjustments - Sony Walkman WM-EX500 Service Manual

SECTION 4

MECHANICAL ADJUSTMENTS

PRECAUTION
1. Clean the following parts with a denatured-alcohol-moistened
swab:
playback head
rubber belts
2. Demagnetize the playback head with a head demagnetizer.
(Do not bring the head demagnetizer close to the erase head.)
3. The adjustments should be performed with the rated power
supply voltage (1.3 V) unless otherwise noted.
Torque Measurement
Mode Torque Meter
FWD CQ-102C
FWD
CQ-102C
Back Tension
REV CQ-102RC
REV
CQ-102RC
Back Tension
FF, REW CQ-201B
pinch roller
capstan
Meter Reading
1.57 – 2.45 mN•m
(16 – 25 g•cm)
(0.23 – 0.34 oz•inch)
0.049 – 0.147 mN•m
(0.5 – 1.5 g•cm)
(0.007 – 0.02 oz•inch)
1.57 – 2.45 mN•m
(16 – 25 g•cm)
(0.23 – 0.34 oz•inch)
0.049 – 0.147 mN•m
(0.5 – 1.5 g•cm)
(0.007 – 0.02 oz•inch)
more than 4.90 mN•m
(more than 50 g•cm)
(more than 0.7 oz•inch)

ELECTRICAL ADJUSTMENTS

1. Specified voltage
2. Setting
BL SKIP
SOUND NORM/MB/GRV : NORM
AVLS
;NR (WM-EX505 only) : OFF
Test tape
Type
WS-48A
Tape Speed Adjustment
Procedure:
Test tape
WS-48A
(3 kHz, 0 dB)
1. Playback WS-48A (tape center) in the FWD state.
2. Adjust RV601 so that the frequency counter reading becomes
3,000 Hz.
Specificated Value: 2,970 to 3,030 Hz
3. Check that deflection of the frequency counter reading between
the beginning and the end of tape is within 1.5% (apporox. 45
Hz).
Adjustment Location:
– MAIN Board (Side B) –
J301
– 12 –
SECTION 5
PRECAUTION
: 1.3 V (DC)
: OFF
: OFF
Signal Used for
3 kHz, 0 dB Tape Speed Adjustment
frequency counter
16
+
set
–
i REMOTE jack (J301)
RV601