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Technical Service Manual
VCR MECHANISM UNIT
(S2-MECHA)
DAEWOO ELECTRONICS CO., LTD.
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1
DESCRIPTION OF THE MECHANISM
1. CHARACTERISTIC OF THE S2-MECHA DECK
1) S2-M ECH A deck satisfies both the VHS and NTS C/PAL specifications.
2) S2-M ECH A deck is driven by three m otors (D rum m otor, Capstan m otor and L/C m otor).
3) S2-M ECH A deck uses the L/C m otor to carry out Front-Loading operation.
4) S2-M ECH A deck has six operating M odes (EJECT, INITIAL, FF/REW, BR AKE, R EVIEW and PLAY m ode),
and each m ode is determ ined by the angular position of the L/C m otor.
5) S2-MECHA deck adopts the Full-Loading system to reduce the mode changing time (especially, picture appearing time).
6) S2-M ECH A deck elim inates the deck PCB and directly connects the 4 m ain parts (Drum m otor, Capstan m otor,
L/C m otor, Cam Switch) to the m ain PC B by using the board-to-board type connectors.
2. NAMES OF MAJOR PARTS
1) TOP VIEW
2
DESCRIPTION OF THE MECHANISM
2) BOTTOM VIEW
3
DESCRIPTION OF THE MECHANISM
3. DESCRIPTION OF THE MODES
1) EJECT MODE
A. As the basis m ode of the deck m echanism , this m ode is closely related to the Cassette-IN/OUT operation;
the Front-Loading (Cassette-IN) operation is initiated and the EJECT (Cassette-OUT) operation is finished in this mode.
Front-Loading Operation : W hen a cassette tape is inserted into the entrance of the front panel w ith a proper inser-
tion force, the L/C m otor is rotated by the insertion force and the deck breaks from the
EJECT m ode. By detecting this event and driving the L/C m otor, the deck can perform the
Front-Loading operation without any additional insertion force.
EJECT operation : W hen the cassette is ejected from the deck, it is locked by the Safety Lever L & R in the C as-
sette Holder Assy so that it can not front-loaded abnorm ally unless the insertion force is
applied again.
B. M echanical Arrangem ent
a. The Band Brake is released from the S Reel Table.
b. The S & T S ub Brake is attached to the S/T-Reel Table.
c. The IDLER GEA R is attached to the S -Reel Table.
EJECT M OD E
4
DESCRIPTION OF THE MECHANISM
2) INITIAL MODE
A. This m ode is the first m ode reached after the E JE CT m ode and represents the unloading state of the deck, which
m eans that the cassette is loaded to the deck but the tape is not yet pulled out from the cassette. This m ode is the
idle m ode at which the deck is posed when power is off during operation.
B. M echanical Arrangem ent
a. The Band Brake is released from the S-Reel Table.
b. The S & T S lant Pole Assy is in the unloading state.
c. The S & T Sub Brake is attached to the S & T-R eel Table.
INITIAL M ODE
5
DESCRIPTION OF THE MECHANISM
3) FF/REW MODE
A. This m ode is for the FF/REW operation of V CR. For fast search, this m ode is configured in the full-loading state
which m eans that the tape is fully pulled out from the cassette and wraps the drum com pletely. The tape loading
operation is carried out as the S & T Slant Pole Assy m oves to the full-loading state. W hen the FF/REW operation is
stopped by the Tape End or S tart sensor, the deck conducts the REVIEW or CUE operation tem porarily.
B. M echanical Arrangem ent
a. The S & T S lant Pole Assy is in the full-loading state.
b. The Band Brake is released from the S-Reel Table.
c. The S & T Sub Brake is released from the S & T Reel Table.
d. The Pinch R oller is released from the Capstan m otor shaft slightly.
FF/REW M O DE
6
DESCRIPTION OF THE MECHANISM
4) BRAKE MODE
A. This m ode, located between the FF/REW m ode and the REVIEW m ode, acts as a transient m ode passed through
tem porarily during the m ode change. The objective of this m ode is to prevent tape slack caused by the high inertial
force of the tape during FF/REW m ode. To do this, the S & T-Reel Table is fastened by the S & T-S ub Brake in this
m ode
B. M echanical Arrangem ent
a. The S & T S lant Pole Assy is in the full-loading state.
b. The Band Brake is released from the S-Reel Table.
c. The S & T Sub Brake is attached to the S & T R eel Table.
d. The Pinch R oller is released from the Capstan m otor shaft slightly.
BRAKE M OD E
7
DESCRIPTION OF THE MECHANISM
5) REVIEW MODE
A. The R eview search operation is perform ed in this m ode. It is obtained by pressing the REV button during Playback
or C ue operation.
B. M echanical Arrangem ent
a. The Band Brake is released from the S-Reel Table.
b. The Pinch R oller is attached to the C apstan m otor shaft.
c. The S-Sub Brake is released from the S-Reel Table.
d. The T-Sub Brake is attached to the T-R eel Table.
REVIEW M OD E
8
DESCRIPTION OF THE MECHANISM
6) PLAY/STOP/CUE/RECORD MODE
A. The PLAY/STOP/CUE/RECO RD m ode perform s the P layback, Stop, C ue and Recording operation. The tape trans-
porting speed m otor is controlled constantly by the Capstan m otor in these operations except the Stop operation,
which is the stand-by operation for others.
B. M echanical Arrangem ent
a. The Band Brake is attached to the S-Reel Table to perform the Tension Servo.
b. The S & T-Sub Brake is released from S & T-Reel Table.
c. The Pinch R oller is attached to the Capstan m otor shaft.
PLAY/STOP/CUE/RECOR D M ODE
9
DESCRIPTION OF THE MECHANISM
4. TIMING CHART OF S2-MECHA DECK
10
DESCRIPTION OF THE MECHANISM
5. S2-MECHA DECK WIRE DIAGRAM
1) WIRE DIAGRAM
11
DESCRIPTION OF THE MECHANISM
2)CONNECTOR PIN ARRANGEMENT
(A) DRUM HEAD (B) FE HEAD (C) ACE HEAD
(2HE AD M ONO)
1 VR 1 1 FE HEAD 1 C T L HE A D (+)
2 COM M ON 2 G ND 2 C T L HE A D (-)
3 V L1 3 A U D IO H E A D
4 G ND 4 A U D IO H E A D
5 GND
6 A U D IO E R A SE
(D) DRUM M O TOR (E) CA PSTAN M OTOR (F) CAM SW ITCH
1 V C C (12V ) 1 VC C (5V) 1 CAM A
2 CONTROL 2 F/R 2 CAM B
3 PG OUT 3 FG -O U T 3 CAM C
4 N O N C O NN E C T 4 CT L-R EF 4 C A M D(G N D)
5 G ND 5 CT L
6 FG OUT 6 I-LIM IT
(G) L/C M OTO R
7 VC C (12V )
8 GND
9 IC G N D 1 L/C M /T (+)
10 NO N C O N N E CT 2 L/C M /T (-)
12
MAINTENANCE
1. MAINTENANCE AND SERVICE SCHEDULE
1) MAINTENANCE AND GENERAL INFORMATION
A. To guarantee the perfect perform ance and the function of S2-M ECHA deck and also to use the tape for the long life,
you should conduct the periodic m aintenance and inspection described below.
- After repairing, Conduct the m aintenance w ithout regard to the tim e used.
B. C leaning of the Drum Head