Mechanical Adjustments; Electrical Adjustments - Sony HCD-EP50 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 magnetizer 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.
• Torque Measurement
Mode Torque Meter
FWD CQ-102C
FWD
CQ-102C
Back Tension
FF CQ-201B
REW CQ-201B
• Tape Tension Measurement
Mode Tension Meter
FWD CQ-403A
pinch roller
rubber belts
idlers
Meter Reading
2.95 – 6.86 mN•m
(30 – 70 g•cm)
(0.42 – 0.97 oz•inch)
0.15 – 5.39 mN•m
(1.5 – 5.5 g•cm)
(0.021 – 0.076 oz•inch)
more than 5.89 mN•m
(more than 60 g•cm)
(more than 0.83 oz•inch)
more than 5.89 mN•m
(more than 60 g•cm)
(more than 0.83 oz•inch)
Meter Reading
more than 100 g
(more than 3.53 oz)
SECTION 5

ELECTRICAL ADJUSTMENTS

PRECAUTION
1. Setting
MEGA BASS switch : OFF
TAPE DECK SECTION
Test tape
Type Signal
WS-48B 3 kHz, 0 dB
P-4-A100 10 kHz, –10 dB
Tape Speed Adjustment
Setting:
Function: TAPE
test tape
WS-48B
(3 kHz, 0 dB)
set
Procedure:
1. Playback WS-48B (tape center) in the FWD state.
2. Adjsut the volume in CAPSTAN/REEL motor so that the fre-
quency counter reading becomes 3,000 Hz.
Specified Value: 2,970 to 3,030 Hz
3. Confirm that the frequency at the beginning and that at the
end of tape winding are between 2,955 to 3,045 Hz.
Adjustment Location:
HCD-EP50
0 dB=0.775 V
Used for
Tape Speed Adjustment
Head Azimuth Adjustment
frequency counter
47 kΩ
+
–
MAIN board
SPEAKER terminal (CN17)
CAPSTAN/REEL
motor
Tape Speed
Adjustment
11