MICROFILM
SERVICE MANUAL
CASSETTE PLAYER
US Model
WM-EX670
AEP Model
UK Model
E Model
WM-EX670/EX672
Model Name Using Similar Mechanism
NEW
Tape Transport Mechanism Type
MT-WMEX672-162
SPECIFICATIONS
WM-EX670/EX672
Dolby noise reduction manufactured under license
from Dolby Laboratories Licensing Corporation.
"DOLBY" and the double-D symbol
a are trade-
marks of Dolby Laboratories Licensing Corporation.
Photo: WM-EX672
Ver 1.1 1999. 05
With SUPPLEMENT 1
(9-926-925-81)
2
TABLE OF CONTENTS
1.
SERVICING NOTES ............................................... 3
2.
GENERAL ................................................................... 5
3.
DISASSEMBLY ......................................................... 6
4.
MECHANICAL ADJUSTMENTS ....................... 11
5.
ELECTRICAL ADJUSTMENTS ......................... 11
6.
DIAGRAMS
6-1. Block Diagram ................................................................ 12
6-2. Printed Wiring Board ...................................................... 14
6-3. Schematic Diagram ......................................................... 17
6-4. IC Pin Function Description ........................................... 22
7.
EXPLODED VIEWS ................................................ 24
8.
ELECTRICAL PARTS LIST ............................... 26
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.
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY MARK
! OR DOTTED
LINE WITH MARK
! 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.
3
SECTION 1
SERVICING NOTES
This set detects the rotation of the idler gear (A) (side S) using the
PH701 (photo reflector). The PH701 is mounted on the MAIN
board, therefore the idler gear (A) (side S) cannot be detected with
the MAIN board removed. As a result, the motor (M901) cannot
be controlled, causing malfunction.
Further, the DIRECTION switch (S701) is also mounted on the
MAIN board, and with the board removed, the mechanism posi-
tion cannot be detected and the operation is not changed over.
Therefor, when the voltage check is executed with the MAIN board
removed, follow the procedure provided below.
1. Setting
(1)
Refer to "3. DISASSEMBLY", and remove the MAIN board.
(2)
Connect the MAIN board to the motor (M901) and the
plunger (PM901) using jumper wires. These can be connected
easily with the use of the extension tool (Part No. 1-769-
143-11) (ten in one set).
(3)
Short the TAPE DETECT switch (S901-1) terminals and the
ATS switch (S901-2) terminals.
(4)
Connect the AF oscillator to the TP53 (P. IN) and the TP14
(GND).
(5)
Supply 1.3 V to the battery terminals using the regulated
power supply.
2. Preset state
To set the PLAY, FF, REW modes, the preset state must be set.
(1)
Check that the slider (NR) and the DIRECTION switch
(S701) are set to the center position. If not, set the preset
state as follow.
(2)
Move the DIRECTION switch (S701) to the side, which the
slider (NR) is facing.
(3)
The slider (NR) will move when the regulated power supply
switch is set to OFF once and then set to ON. Move the DI-
RECTION switch (S701) according to this timing and set to
the center position.
3. FF, REW modes
(1)
Check that the preset state is set.
(2)
Input the square wave or sine wave to the TP53 (P. IN) and
the TP14 (GND).
(3)
Press the
p button (S702) to set the STOP mode.
(4)
Press the [FF AMS] button (S704) or the [REW AMS] but-
ton (S705).
4. PLAY mode
(1)
Check that the preset state is set.
(2)
Input the square wave or sine wave to the TP53 (P. IN) and
the TP14 (GND).
(3)
Press the
p button (S702) to set the STOP mode.
(4)
Press the [ REPEAT] button (S703) will move the
slider (NR) once towards the side R and then to the side F.
Move the DIRECTION switch (S701) according to this tim-
ing will set the PLAY mode (side F). Press the
[ REPEAT] button (S703) another time and move
the DIRECTION switch (S701) according to the movement
of the slider (NR) will set the PLAY (R mode).
Note 1: If the above fails, perform from preset again.
Note 2: Use the [ REPEAT] (S703),
p (S702), [FF AMS]
(S704), and [REW AMS] (S705) buttons on the remote control-
ler as much as possible. If no remote controller, do not touch the
buttons with your hands, but using a stick with a round tip.
Note 3: When using headphones, the timing for move the DIRECTION
switch (S701) can be determined from the beep sound.
9 (
9 (
9 (
+
FF AMS
(S704)
connect to the plunger
(PM901)
battery
terminal
'
battery
terminal
`
square wave
(sine wave)
10 Hz, 3.5 dB
AF oscillator
TAPE DETECT
(S901-1)
MAIN Board (side B)
ATS
(S901-2)
REW AMS
(S705)
TP14
(GND)
S701
DIRECTION
FWDNSTOPnREV
oe REPEAT
(S703)
p
(S702)
PH701
TP53 (P.IN)
connect to the
motor (M901)
4
Slider (NR)
Rotation system
Rotation system during PLAY.
Rotation system during FF.
Rotation system during REW.
slider (NR)
side F side R
center
insert flywheel (N)
insert flywheel (R)
reverse pulley
clutch assy (F)
gear (Y)
cam gear
gear (REEL) (side T)
motor pulley
idler gear (A) (side T)
gear (FR)
(FF: left side)
insert flywheel (N)
insert flywheel (R)
reverse pulley
clutch assy (F)
idler gear (B)
gear (Y)
cam gear
gear (REEL) (side T)
gear (REEL) (side S)
motor pulley
idler gear (A) (side T)
idler gear (A) (side S)
gear (NR)
(FWD : left side/
REV : right side)
insert flywheel (N)
insert flywheel (R)
reverse pulley
clutch assy (F)
gear (Y)
cam gear
gear (REEL)
(side S)
motor pulley
idler gear (A)
(side S)
gear (FR)
(REW: right side)
5
SECTION 2
GENERAL
This section is extracted from
instruction manual.