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SERVICE MANUAL
CASSETTE-CORDER
US Model
TCM-20DV/21DV/22DV/23DV
Canadian Model
TCM-20DV/22DV
AEP Model
TCM-20DV/21DV
E Model
TCM-20DV/23DV
Chinese Model
TCM-20DV
SPECIFICATIONS
TCM-20DV/21DV/
22DV/23DV
Model Name Using Similar Mechanism
NEW
Tape Transport Mechanism Type
MT-20DV-118
Photo: TCM-20DV
Supplied accessories
The instructions in this manual are for
4 models.
The TCM-20DV is the model used for
illustration purposes.
TCM-
23DV 22DV 21DV 20DV
AC power adaptor (1)
--
a
----
Battery charger adaptor (1) --
a
----
Rechargeable batteries (2)
--
a
----
(NC-AA, 1.2V, 700mAh,
Ni-Cd)
Cassette tape C-90 (1)
----
a
--
Battery LR6 (2)
----
a
--
Monaural microphone (1)
----
a
--
Super-directional
a
----
--
microphone (1)
Carrying pouch (1)
----
a
--
Hand strap (1)
aaa
a
(attached to the unit)
Battery life (Approx. hours) (EIAJ*)
Playback
Recording
Sony alkaline
LR6 (SG)
11
11
Sony R6P (SR)
3
3
Sony
rechargeable
battery
33
(NC-AA) fully
charged (TCM-
22DV only)
* Measured value by the standard of
EIAJ (Electronic Industries
Association of Japan). (Using a Sony
HF series cassette tape and playing
back with speakers)
Note
The battery life may shorten
depending on the operation of the
unit.
For maximum performance we
recommend that you use alkaline
batteries.
House Current (see Fig. A- )
Connect the AC power adaptor to
DC IN 3V and to a wall outlet. The
AC power adaptor is supplied only
with the TCM-22DV. For other
models, use the AC-E30HG AC
power adaptor (not supplied). Do
not use any other AC power
adaptor.
Polarity of
the plug
Note
Specifications for AC-E30HG vary for
each area. Check your local voltage
and the shape of the plug before
purchasing.
Recording system
2-track 1 channel monaural
Tape speed
4.8 cm/s or 2.4 cm/s
Frequency range
250 - 6,300 Hz using nomal (TYPE
I) cassette (with REC TIME switch
at "NORMAL")
Speaker
Approx. 3.6 cm (1 7/
16 in.) dia.
Power output
250 mW (at 10 % harmonic
distortion)
Input
Microphone input jack (minijack)
sensitivity 0.2 mV for 3 kilohms or
lower impedance microphone
Output
Earphone jack (minijack) for 8 - 300
ohms earphone
Variable range of the tape speed
From approx. +30% to ­15% (with
REC TIME switch at "NORMAL")
Power requirements
3 V DC batteries R6 (AA)
× 2/
External DC 3 V power sources
Dimensions (w/h/d) (incl. projecting
parts and controls)
Approx. 112
× 36.6 × 90.3 mm
(4 1/2 × 1 1/2 x 3 5/8 in.)
Mass
Approx. 175 g (6.2 oz.)
Design and specifications are subject
to change without notice.
Ver 1.0 2000. 02


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­ 2 ­
TABLE OF CONTENTS
1.
SERVICING NOTES ............................................... 2
2.
GENERAL ................................................................... 3
3.
DISASSEMBLY ......................................................... 4
4.
MECHANICAL ADJUSTMENTS ....................... 7
5.
ELECTRICAL ADJUSTMENTS ......................... 8
6.
DIAGRAMS
6-1. Block Diagram ................................................................
9
6-2. Printed Wiring Board ...................................................... 11
6-3. Schematic Diagram ......................................................... 13
7.
EXPLODED VIEWS ................................................ 16
8.
ELECTRICAL PARTS LIST ............................... 19
Flexible Circuit Board Repairing
· Keep the temperature of the soldering iron around 270 °C dur-
ing repairing.
· Do not touch the soldering iron on the same conductor of the
circuit board (within 3 times).
· Be careful not to apply force on the conductor when soldering
or unsoldering.
Notes on chip component replacement
· Never reuse a disconnected chip component.
· Notice that the minus side of a tantalum capacitor may be dam-
aged by heat.
ATTENTION AU COMPOSANT AYANT RAPPORT
À LA SÉCURITÉ!
LES COMPOSANTS IDENTIFIÉS PAR UNE MARQUE 0
SUR LES DIAGRAMMES SCHÉMATIQUES ET LA LISTE
DES PIÈCES SONT CRITIQUES POUR LA SÉCURITÉ
DE FONCTIONNEMENT. NE REMPLACER CES COM-
POSANTS QUE PAR DES PIÈCES SONY DONT LES
NUMÉROS SONT DONNÉS DANS CE MANUEL OU
DANS LES SUPPLÉMENTS PUBLIÉS PAR SONY.
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY MARK 0 OR DOTTED
LINE WITH MARK 0 ON THE 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 PUB-
LISHED BY SONY.
SECTION 1
SERVICING NOTES
In this set, the S102 (POWER) detects REC/PLAYBACK on.
It is mounted on the MAIN board, and therefore the REC/PLAY-
BACK on cannot be detected with the MAIN board removed.
When making an operation check and voltage check of mechani-
cal deck with the MAIN board removed, fix the S102 at turn on.
­ MAIN BOARD (Conductor Side) ­
S102
on


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­ 3 ­
SECTION 2
GENERAL
This section is extracted from
instruction manual.
· Location of Controls
REC TIME
MIC
VOL
B
PLAY
M
FF/CUE
SPEED CONTROL
EAR
VOR
z
REC
x
STOP
m
REW/
REVIEW
PAUSE
DC IN 3 V
.
Built-in mic
BATT


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­ 4 ­
CABINET (REAR), CASSETTE LID
Note: Follow the disassembly procedure in the numerical order given.
SECTION 3
DISASSEMBLY
· This set can be disassembled in the order shown below.
SET
CABINET (REAR), CASSETTE LID
MAIN BOARD, MECHANISM DECK (MT-20DV-118)
BELT
9
cassette lid
INSTALLATION CASSETTE SPRING
cabinet front
5
hand strap
3
claw
3
four claws
2
screw
(IB lock)
4
cabinet (rear)
1
three screws
(B1.7
× 9)
7
boss
7
boss
6
Remove the six solders.
cassette lid
cassette spring


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­ 5 ­
MAIN BOARD, MECHANISM DECK (MT-20DV-118)
BELT
6
claw
2
screw
(1.7)
3
screw
(M1.4)
4
MAIN board
7
mechanism deck
(MT-20DV-118)
5
three screws
(IB lock)
1
Remove the two solders
electret condenser microphone
(MIC101).
1
Remove the two solders
magnetic head (HRP901).
1
Remove the two solders
motor (M901).
1
belt (capstan)
2
belt (FR)
capstan belt
FR belt
pulley (FR) assy
flywheel assy
motor DC