Sony CFM-20L Service Manual ▷ View online
5
CFM-20L
2-5. BATT (+) BOARD, POWER BOARD
1
2
4
Claw
3
Screws
(+ BVTP 3X10)
(+ BVTP 3X10)
Power board
Batt (+) board
Red
White
Cabinet (rear)
•
DIAL POINTER SETTING
1
2
5
7
Cabinet (front)
Pointer
Cabinet (front)
Cabinet (front)
Scrached line
ECM101
Set the leads from microphone(ECM101)
as shown in the figure.
as shown in the figure.
Set Pointer to "Cabinet
(front)" as shown in the
figure.
(front)" as shown in the
figure.
4
Set the right side edge
of Pointer to the scratched line
on Cabinet (front).
on Cabinet (front).
3
Screws
6
Turn knob (tune) fully in the
direction of the arrow as shown
in the figure.
direction of the arrow as shown
in the figure.
Cabinet (rear) ASSY
Cabinet (front)
(+BVTP 3X10)
Pointer
Back plate
Note : Follow the installation procedure in the numerical order given.
6
CFM-20L
TAPE RECORDER SECTION
FUNOTION switch (S101)
: TAPE (RADIO OFF)
VOLUME (RV101)
: MIN
Standard Output Level
Output terminal
Earphone jack (J101)
load impedance
8
Ω
output signal level
0.25V (–10dB)
Test Tape
Type
Signal
Used for
WS-48A
3kHz, 0dB
Tape Speed Adjustment
P-4-A063
6.3kHz
Record/Playback Head
Azimuth Adjustment
Record/Playback Head Azimuth Adjustment
Procedure :
1.Playback Mode
Procedure :
1.Playback Mode
2.Rotate the screw to adjust level meter reading to the maximum.
Note :
Note :
Adjust to the maximum peak though there may be two or
three peakes
three peakes
3.After the adjustment, lock the adjustment screws with suitable
locking compound.
Adjustment Location :
SECTION 3
ADJUSTMENTS
3-1. MECHANICAL ADJUSTMENTS
PRECAUTION
1.Clean the following parts with a denatured-alcohol-moistened
swab :
record/playback head
pinch roller
erase head
rubber belts
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
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
Forward
CQ-102AS
Forward
CQ-102AS
Back Tension
Fast Forward
CQ-201WS
Rewind
CQ-201WS
Tape Tension Measurement
Torque Meter
Meter Reading
Torque
Torque Meter
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)
3-2. ELECTRICAL ADJUSTMENTS
CQ-405AS
more than 60g
(more than 2.12 oz)
(more than 2.12 oz)
0dB=0.775V
Head azimuth adjustment screw
set
test tape
P-4-A063J
(6.3kHz, -10dB)
P-4-A063J
(6.3kHz, -10dB)
8
Ω
level meter
J101 (Earphone jack)
+
7
CFM-20L
FM Section
Function switch (S101)
: FM
Volume
: MIN
Tape Speed Adjustment
Procedure :
Mode : Playback
Procedure :
Mode : Playback
Adjustment Value :3,000Hz
Standard Value
Standard Value
:2,960 to 3,040Hz
Frequency difference between the beginning and the end of the tape
should be within 1.0% (30Hz).
should be within 1.0% (30Hz).
Adjustment Location :
TUNER SECTION
LW Section
Function switch (S101)
: LW
Volume
: MIN
CT3, CT4
: mechanical center
0dB=1
µV
set
test tape
WS-48B
(3kHz, 0dB)
WS-48B
(3kHz, 0dB)
digital frequency
counter
counter
J101 (Earphone jack)
8
Ω
+
tape speed adjustment
control inside motor
control inside motor
AM RF signal
generator
generator
30% amplitude modulation by 400Hz
signal.
Output level : as low as possible
signal.
Output level : as low as possible
Put the lead-wire
antenna close to
the set.
antenna close to
the set.
set
+
level meter
J101 (Earphone jack)
8
Ω
set
+
level meter
J101 (Earphone jack)
8
Ω
FM RF signal
generator
generator
75kHz frequency deviation by
1kHz signal.
Output level : as low as possible
1kHz signal.
Output level : as low as possible
telescopic
antenna
terminal
antenna
terminal
0.01 F
µ
8
CFM-20L
• Repeat the procedures in each adjustment several times, and the
frequency coverage and tracking adjustments should be finally
done by the trimmer capacitors.
done by the trimmer capacitors.
LW IF ADJUSTMENT
Adjust for a maximum reading on level meter.
T1
455kHz
LW FREQUENCY COVERAGE ADJUSTMENT
Adjust for a maximum reading on level meter.
L4
145kHz
CT6
300kHz
LW TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter.
L3
160kHz
CT5
260kHz
FM FREQUENCY COVERAGE ADJUSTMENT
Adjust for a maximum reading on level meter.
L2
87.00MHz
CT1
108.30MHz
FM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter.
L1
87.00MHz
CT2
108.30MHz
Adjustment Location : MAIN board
FM IF ADJUSTMENT
Adjust for a maximum reading on level meter.
L5
10.7MHz
[MAIN BOARD]
(Conductor side)
(Conductor side)
CT3 : LW Frequency Coverage Adjustment
(Set to mechanical center)
(Set to mechanical center)
CT4 : LW Tracking Adjustment
(Set to mechanical center)
(Set to mechanical center)
CT2: FM Tracking Adjustment
CT1 : FM Frequency
Coverage Adjustment
Coverage Adjustment
[MAIN BOARD]
(Component side)
(Component side)
L5 : FM IF Adjustment
T1: LW IF Adjustment
L1: FM Tracking Adjustment
L3: LW Tracking Adjustment
L4 : LW Frequency
Coverage Adjustment
Coverage Adjustment
CT5 : LW Tracking Adjustment
CT6 : LW Frequency
Coverage Adjustment
Coverage Adjustment
L2: FM Frequency
Coverage Adjustment
Coverage Adjustment
Click on the first or last page to see other CFM-20L service manuals if exist.