Sony CFM-20L User manual

Ver 1.0 2001.04

CFM-20L

SERVICE MANUAL

RADIO CASSETTE-CORDER

SPECIFICATIONS

AEP Model

9-873-114-11

2001D0200-1

Sony Corporation

Personal Audio Company

Shinagawa Tec Service Manual Production Group

Model Name Using Similar Machanism CFM-20

Tape Transport Mechanism Type MF-M20-117

CFM-20L

TABLE OF CONTENTS

Specifications ........................................................................... 1

1. GENERAL

Location and Function of Controls .................................... 2

2. DISASSEMBLY

2-1. Cabinet (Front) Sub ASSY, Cabinet (Rear) ASSY .... 3

2-2. MD ASSY ................................................................... 3

2-3. Record/Playback Head (HRP101),

Reel/Capstan Motor (M101),Belt ............................... 4

2-4. Jack Board, Main Board ............................................. 4

2-5. Batt (+) Board, Power Board ...................................... 5

3. ADJUSTMENTS

3-1. Mechanical Adjustments ............................................. 6

3-2. Electrical Adjustments ................................................ 6

4. DIAGRAMS

4-1. Block Diagrams .......................................................... 9

4-2. Printed Wiring Boards .............................................. 10

4-3. Schematic Diagrams -Main Section (1/2) - .............. 11

4-4. Schematic Diagrams -Main Section (2/2) - ............. 12

5. EXPLODED VIEWS

5-1. Front Cabinet Section ............................................... 15

5-2. Rear Cabinet Section ................................................ 16

5-3. Mechanism Deck Section-1(MF-M20-117) ............. 17

5-4. Mechanism Deck Section-2(MF-M20-117) ............. 18

6. ELECTRICAL PARTS LIST ........................................ 19

SECTION 1

GENERAL

SAFETY-RELATED COMPONENT WARNING!!

COMPONENTS IDENTIFIED BY MARK !OR DOTTED LINE WITH

MARK !ONTHE SCHEMATIC DIAGRAMS AND IN THE PARTS LIST

ARE CRITICAL TO SAFE OPERATION.

REPLACE THESE COMPONENTS WITH SONY PARTS WHOSE

PART NUMBERS APPEAR AS SHOWN IN THIS MANUAL OR IN

SUPPLEMENTS PUBLISHED BY SONY.

This section is extracted from

instruction manual.

Location and Function of Controls

Notes on chip component replacement

• Never reuse a disconnected chip component.

• Notice than the minus side of a tantalum capactior may be

damaged by heat.

CFM-20L

SECTION 2

DISASSEMBLY

Note : Follow the disassembly procedure in the numerical order given.

2-2. MD ASSY

• The equipment can be removed using the following procedure.

Set

Cabinet (front) sub ASSY

Cabinet (rear) ASSY Jack board, Main board Batt(+) board, Power board

MD ASSY

Record/playback head (HRP101),

Reel/capstan motor (M101), Belt

Screws (+ BVTP 3X14)

Screws

(+ BVTP 3X14

)

Remove solder (two place)

CNP103

Cabinet (front) sub ASSY

Lid, BATT

Cabinet (rear) ASSY

White

White/red

CNP102

Screw (+ BVTP 3X10)

CNP101

MD ASSY

Bracket (VOL)

Cabinet (rear) ASS

2-1. CABINET (FRONT) SUB ASSY, CABINET (REAR) ASSY

CFM-20L

2-3. RECORD/PLAYBACK HEAD (HRP101), REEL/CAPSTAN MOTOR (M101), BELT

2-4. JACK BOARD , MAIN BOARD

Screws Tapping+B

(+PTT 2X5(s))

MD ASSY

Record/playback

head (HRP101)

Reel/capstan

motor (M101)

MD ASSY M101

Belt

Flywheel ASS

• Attaching belt

Spring, Compr

Screws

+ PTT 2X 5

Screw + P2.6X 5

Belt

Lug (T), plate

Guide, tape

Screw

(+ BVTP 3X10)

Screw

(+ BVTP 3X10)

Jack board

CNP901

Main board

Cabinet (rear

)

Knob (VOL)

Knob (FUN)

Chassis

Bracket (PWB)

Screw

(+ BVTP 3X10)

CFM-20L

2-5. BATT (+) BOARD, POWER BOARD

Claw

Screws

(+ BVTP 3X10)

Power board

Batt (+) board

Red

White

Cabinet (rear

)

•DIAL POINTER SETTING

Cabinet (front) Pointer

Cabinet (front)

Scrached line

ECM101

Set the leads from microphone(ECM101)

as shown in the figure.

Set Pointer to "Cabinet

(front)" as shown in the

figure.

Set the right side edge

of Pointer to the scratched line

Cabinet (front)

Screws

Turn knob (tune) fully in the

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.

CFM-20L

TAPE RECORDER SECTION

FUNOTION switch (S101) : TAPE (RADIO OFF)

VOLUME (RV101) : MIN

Standard Output Level

Output terminal Earphone jack (J101)

load impedance 8Ω

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

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 :

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

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)

0dB=0.775V

Head azimuth adjustment screw

set

test tape

P-4-A063J

(6.3kHz, -10dB) 8

Ω

level meter

J101 (Earphone jack

)

CFM-20L

FM Section

Function switch (S101) : FM

Volume : MIN

Tape Speed Adjustment

Procedure :

Mode : Playback

Adjustment Value :3,000Hz

Standard Value :2,960 to 3,040Hz

Frequency difference between the beginning and the end of the tape

should be within 1.0% (30Hz).

Adjustment Location :

TUNER SECTION

LW Section

Function switch (S101) : LW

Volume : MIN

CT3, CT4 : mechanical center

0dB=1µV

set

test tape

WS-48B

(3kHz, 0dB)

digital frequency

counter

J101 (Earphone jack)

8Ω

tape speed adjustment

control inside motor

AM RF signal

generator

30% amplitude modulation by 400Hz

signal.

Output level : as low as possible

Put the lead-wire

antenna close to

the set.

set

level mete

J101 (Earphone jack)

8Ω

set

level mete

J101 (Earphone jack)

8Ω

FM RF signal

generator

75kHz frequency deviation by

1kHz signal.

Output level : as low as possible

telescopi

antenna

terminal

0.01 F

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.

LW IF ADJUSTMENT