Adjustments; Mechanical Adjustments; Electrical Adjustments - Sony CFM-20L Service Manual

CFM-20L

3-1. 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 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.
5. The adjustments should be performed with the rated power
supply voltage unless otherwise noted.
Torque Measurement
Torque Torque Meter
Forward CQ-102AS
Forward
CQ-102AS
Back Tension
Fast Forward CQ-201WS
Rewind CQ-201WS
Tape Tension Measurement
Torque Meter
CQ-405AS
6
SECTION 3

ADJUSTMENTS

pinch roller
rubber belts
Meter Reading
1.77 to 5.88 mN•m
(18 to 60 g•cm)
(0.25 to 0.83 oz•inch)
0.01 to 0.49 mN•m
(1 to 5 g•cm)
(0.014 to 0.069 oz•inch)
4.42 to 9.31 mN•m
(45 to 95 g•cm)
(0.63 to 1.31 oz•inch)
4.42 to 9.31 mN•m
(45 to 95 g•cm)
(0.63 to 1.31 oz•inch )
Meter Reading
more than 60g
(more than 2.12 oz)

3-2. ELECTRICAL ADJUSTMENTS

TAPE RECORDER SECTION
FUNOTION switch (S101) : TAPE (RADIO OFF)
VOLUME (RV101)
Standard Output Level
Output terminal
load impedance
output signal level
Test Tape
Type Signal
WS-48A 3kHz, 0dB
P-4-A063 6.3kHz
Record/Playback Head Azimuth Adjustment
Procedure :
1.Playback Mode
test tape
P-4-A063J
(6.3kHz, -10dB)
set
2.Rotate the screw to adjust level meter reading to the maximum.
Note :
Adjust to the maximum peak though there may be two or
three peakes
3.After the adjustment, lock the adjustment screws with suitable
locking compound.
Adjustment Location :
Head azimuth adjustment screw
0dB=0.775V
: MIN
Earphone jack (J101)
8Ω
0.25V (–10dB)
Used for
Tape Speed Adjustment
Record/Playback Head
Azimuth Adjustment
level meter
8 Ω
+
J101 (Earphone jack)