Servicing Notes - Sony WM-EX660 Service Manual

This set detects the rotation of GEAR (PH) using the PH701 (photo
reflector). The PH701 is mounted on the MAIN board, and there-
fore the GEAR cannot be detected with the MAIN board removed.
As a result, the motor cannot be controlled, causing malfunction.
Further, the S702 (FWD/REV switch) is also mounted on the MAIN
board, and with the board removed, the mechanism position
cannnot be detected and the operation is not changed over.
Therefore, when the voltage check is executed with the MAIN
board removed, follow the procedure provided below.
Note : Do not move the S702 swithc position when removing the MAIN
board.
If it is moved, the set will not be changed over to the selected mode.
In this case, reconnect the MAIN board to the set and retry the
work from the beginning.
— MAIN BOARD (SIDE B) —
S702
FWD → REV
S706 (FF)
S707 (REW)
connect to
RV601
M901 (motor)
battery terminal
SECTION 1

SERVICING NOTES

square wave
10 Hz, – 3.5 dB
IC701
TP35
PHOTO
IN
PH701
battery terminal
1. Setting
1) Refer to "3. DISASSEMBLY", and remove the cabinet and
open the MAIN board.
2) Connect the MAIN board to the M901 (motor) and PM901
(plunger) using jumper wires.
3) Short the ATS terminals.
4) Press and fixed the S701 (CASSETTE HOLDER).
5) Supply 1.5V to the battery terminals ' and ' using a stabi-
lized power supply.
2. FF, REW Modes
1) Input a square wave to the TP35 (PHOTO IN) and TP23
(GND). (See figure below)
2) Press the S704 (STOP) for selecting STOP mode.
3) Press the S706 (FF) or S707 (REW).
3. PLAY mode
1) Input a square wave to the TP35 (PHOTO IN) and TP23
(GND). (See figure below)
2) Press the S704 (STOP) for selecting STOP mode.
3) Press the S705 (PLAY). (Each time the switch is pressed, the
mode is changed over.)
AF
oscillator
TP23
(GND)
S705 (PLAY)
S704 (STOP)
ATS terminals
(to S901)
– 3 –
+
–
S701
CASSETTE
HOLDER
connect to
PM901 (plunger)