Section 2. Service Note - Sony WM-GX510 Service Manual

[Service Mode]
Mode which enables the mechanism to be operated with the
MAIN board opened.
Photo sensor PH701 mounted on the MAIN board is used to
detect rotaion of the reels. Because it is mounted on the MAIN
board, when the MAIN board is being removed, rotation of the
reels cannot be detected and the auto-off/tape-end detector
circuit does not operate correctly.
F/R switch (S701) is also mounted on the MAIN board.
Therefore, without the MAIN board, the head cannnot be
placed in playback position, and power cannot be supplied to
the circuitry of the playback system.
When the MAIN board is being removed, follow the
procedures below, in order to check operation of the
mechanisms of the tape deck and to check voltages supplied to
each circuit.
1. Setting
1) Refer to "Disassembly" and remove the cabinet and open
the MAIN board.
2) Connect the MAIN board to the motor and plunger using a
jumper wire. Use "Extension tool (1-769-143-11)) (one set
10 tools)" to make connection simple.
3) Short-circuit the service mode land (4 points) by soldering.
4) Apply a square wave signal to TP20. (See the figure on the
right.)
5) Supply 1.5V to the battery terminals (+) and (–) using a
DC power supply.
2. Preset State
This state must be set to set the PLAY, FF, and REW
modes.
1) Check that the lever (NR SW) is at the center and F/R
switch (S701) is at the center. If not, set the preset state as
follows.
2) Move the F/R switch (S701) according to the side faced by
the lever (NR SW).
3) Turn OFF the DC power supply switch once and then turn
it ON again so that the lever (NR SW) can be moved.
Move the F/R switch (S701) according to this timing and
set to the center.
3. FF REW Mode
1) Set the preset state and press the FF switch and REW
switch.
4. PLAY Mode
1) Set the preset state.
2) Press the œ switch. The lever (NR SW) will move to the
F side once and then to the R side. Move the F/R switch
(S701) according to this timing to set the PLAY (R side)
mode. Press the œ switch another time and move the F/
R switch (S701) according to the movement of the lever
(NR SW) to set the PLAY (F side) mode.
Note 1 : If the above cannot be performed, start again from
preset.
Note 2 : Use the remote control œ , p , FF, and REW
switches as much as possible. If the remote control is
not available, do not touch S703 to S706 with the
hand and use something with a round tip to press
them.
SECTION 2
SERVICE NOTE
[MAIN Board]
— Side A —
AF OSCILLATOR
Connect to
plunger
S713
(ENTER)
S712
(TUNING –)
S711
(TUNING +)
S707
(RADIO ON
BAND)
— Side B —
[Lever (FR SW)]
— 4 —
SQUARE WAVE (SINE WAVE)
10Hz
3.5 dB (1.5V)
Battery Terminal (–)
Service mode land
S709 S710
(MENU)
(SET)
S703
(RADIO OFF p)
S706
(AMS REW
PRESET –)
S704 TP20
(REPEAT œ)
S705
(AMS FF
PRESET +)
Service
mode land
PH701
S701 F/R SWITCH
(FWD N STOP n REV)
F side
R side
Center
Center
F side
R side
Battery
Terminal (+)
Connect to
motor
S702
(HOLDER
SWITCH)
S714
(C HOLD)
HOLD