DOWNLOAD Sharp CD-E250 (serv.man20) Service Manual ↓ Size: 3.52 MB | Pages: 68 in PDF or view online for FREE

– 10 –

Perform steps 1, 2, 3, 10,11, and 12 of the disassembly
method to remove the CD mechanism.

1. Remove the screws (A1) x 2 pcs.
2. Remove the belt (A2) x 1 pc.
3. Remove the screws (A3) x 2 pcs., to remove the T/T  rotate

motor.

(A1)x2
ø2.4x3mm

(A3)x2
ø3x10mm

(A2)x1

Loading Tray
(Bottom View)

Loading Tray

T/T Motor  PWB

T/T Rotate Motor

(B1)x2
ø2.4x5mm

Up/Down Loading Motor

CD Player Unit

(B2)x1

1. Remove the screws (B1) x 2 pcs.
2. Remove the belt (B2) x 1 pc.

Perform steps 1, 2, 3, 10and 13 of the disassembly method to
remove the CD mechanism.
1. Remove the screws (C1) x 4 pcs., to remove the mechanism

unit.

Note
After removing the connector for the optical pickup from the
connector wrap the conductive aluminium foil around the front
end of connector so as to protect the optical pickup from
electrostatic damage.

Holder

CD Mechanism Unit

Holder
PWB

(C1)x4
ø2.5x10mm

– 11 –

•••••

Play: DM-300

Tape 1: Over 80 g
Tape 2: Over 80 g

•••••

Play: DM-300

10 to 20 g.cm

10 to 20 g.cm

Fast forward: DM-300

—

Over 50 g.cm

Rewind: DM-300

—

Over 50 g.cm

Tape

TCC-119

Variable

3,000 

±

 30 Hz

Speaker

speed

Resistor in

Terminal

motor.

(Load
resistance:
6 ohms)

•••••

Tape
Motor

Variable Resistor in Motor

TAPE MECHANISM

FM IF

FM RF

VR351

FM MUTE
Level

T351

AM IF

T302

T306

T304

IC301

IC302

L303

L302

CNP301

FM BAND
COVERAGE fL

AM BAND
COVERAGE fL

AM TRACKING
fL

MAIN PWB

1

1

11

12

22

20

R381

R356

R357

TP301

TP302

IF

450 kHz

1,620 kHz

T351

*1

 AM Band

—

522 kHz

(fL): T306

*2

Coverage

1.1 

±

 0.1 V

AM

990 kHz

990 kHz

T302

*1

Tracking

fL: Low-range frequency
fH: High-range frequency

Signal generator: 400 Hz, 30%, AM modulated

*1. Input: Antenna

Output: Speaker terminal

*2. Input: Input is not connected

Output: TP301

98.00 MHz

98.00 MHz

VR351*1

Input: CNP301

(30 dB

µ

V)

Output: Speaker
Terminal

• FM Mute Level
Signal generator: 1 kHz, 40 kHz dev., FM modulated

*1. Adjust so that an output signal appears.

• FM RF
Signal generator: 1 kHz, 75 kHz dev., FM modulated

FM Band

—

87.50 MHz

(fL): L303

*1

Coverage

3.4 

±

 0.1 V

FM RF

98.00 MHz

98.00 MHz

L302

*2

(10~30 dB)

*1. Input: Antenna,

Output: TP301

*2. Input: Antenna,

Output: Speaker Terminal

• FM Detection
Signal generator: 10.7 MHz, FM sweep generator

FM IF

10.7 MHz

98.00 MHz

T304(Turn

Input: Pin 1 of

the core of

IC301

T304 fully
counter-
clockwise).

87.5 MHz

87.5 MHz

2.2 V 

±

 1.0 V

TP301

108 MHz

108 MHz

7.8 V 

±

 1.0 V

TP301

• Check FM VT
Signal generator: 1 kHz, 40 kHz dev., FM modulated

– 12 –

The test mode applied to this microcomputer has three modes,
namely the ordinary test mode for adjustment or measurement,
the aging test mode, and the self-diagnosis test mode for self-
judgment in case of final product inspection.

For obtaining each test mode, press the ON/STAND BY
button, while keeping pressing the following two buttons in
the ordinary stand-by mode (power off ).  In this case, the
main unit buttons are valid.  When turning the POWER on
with remote control buttons, test modes are not obtained.

[Ordinary test mode]
1. CD Test Mode (TEST 1) ..........................................

CD + VOLUME UP

2. Tuner Test Mode (TEST 2) ......................................

TUNER(BAND) + VOLUME UP

3. Electronic Volume Test Mode (TEST 3) ..................

TUNING DOWN + VOLUME UP

4. Timer Test Mode (TEST 4) ......................................

TIMER/SLEEP + VOLUME DOWN

5. FL Test Mode (TEST 5) ...........................................

CLOCK + VOLUME DOWN

6. CD MECHANISM Aging Test Mode (TEST 8) ........

MEMORY/SET + VOLUME DOWN

In the CD test mode the operation of each step is possible
even if the LID-SW is off.  If focus cannot be taken in step
3 or any error is processed, it is impossible to proceed to
the next step.  During error processing, end the test mode
by pressing the ON/STAND BY button or return to the step
1 by pressing the CD STOP button.  Any other operations
are inhibited.
1. Step 1 Mode
When the CD test mode is obtained, the following display
lights up.  Then CD initialization operation flow proceeds
up to CD STB off to wait for the following buttons to be
pressed.

[Self-diagnosis Test Mode]

1.  Button input diagnosis test mode (TEST 6) .…....

TUNNIG UP + VOLUME UP

Processes are different depending on destinations at initial
settings.

One second after display lights up

Press the following buttons in this state to obtain the
operations specified below.

"ON/STAND BY" ...... Test mode and power turned off to

shift to the ordinary standby mode.

"FF/FWD" ................. After the pickup returns to the

innermost periphery, it slides toward
the outer periphery while this button
is pressed.

"REW/REV" .............. After the pickup returns to the

innermost periphery, it slides toward
the inner periphery while this button
is pressed.  If PICKUP IN is on, input
is invalid.

"MEMORY/SET" ...... Shift to step 2
"STOP" ..................... Invalid
"VIDEO/AUX" ........... CLV

2. Step 2 Mode
Press the "MEMORY/SET" button in this mode to transmit
the laser lighting command LDON (8400) and turn on the
laser.  Any other operations are not performed in this case.

Press the following buttons in this state to obtain the
operations specified below.
"ON/STAND BY" ..... Test mode and power turned off to

shift to the ordinary standby mode.

"FF/FWD" ................ The pickup slides toward the outer

periphery while this button is pressed.

"REW/REV" ............. The pickup slides toward the inner

periphery while this button is pressed.
If PICKUP IN is on, input is invalid.

"MEMORY/SET" ...... Shift to step 3

While the laser keeps lighting, CD initialization operation
flow proceeds up to 'CLV servo ON' to wait for the
following buttons to be pressed.(Focus servo turned on
for focus search)
The focus search is repeated to take focus.

Press the following buttons in this state to obtain the
operations specified below.
"ON/STAND BY" ..... Test mode and power turned off to

shift to the ordinary standby mode.

"FF/FWD" ................ The pickup slides toward the outer

periphery while this button is pressed.

"REW/REV" ............. The pickup slides toward the inner

periphery while this button is pressed.
If PICKUP IN is on, input is invalid.

"MEMORY/SET" ...... If focus has been taken, shift to step 4

is executed. If not, acceptance is
inhibited.

*If the focus is not received after it has been taken, the
process returns to step 1.

– 13 –

The CLV servo ON command (8600) is transmitted to
wait for the following buttons to be pressed. (The disc is
rotated for CLV lock.)

The time display always indicates "0:00".

Press the following buttons in this state to obtain the
operations specified below.
"ON/STAND BY" ..... Test mode and power turned off to

shift to the ordinary standby mode.

"FF/FWD" ................ The pickup slides toward the outer

periphery while this button is pressed.

"REW/REV" ............. The pickup slides toward the inner

periphery while this button is pressed.
If PICKUP IN is on, input is invalid.

"MEMORY/SET" ...... Return to step 5

*If the focus is not received, the process returns to step 1.

When the CD initialization operation flow is completed,
the mute is turned off, and playback is started.  Even if
playback reaches the outermost periphery of disc, the
operation does not stop. The LCD display indicates the
playback passage time as in case of ordinary CD
playback.

Press the following buttons in this state to obtain the
operations specified below.

"ON/STAND BY" ...... Test mode and power turned off to

shift to the ordinary standby mode.

"FF/FWD" ................. The pickup slides toward the outer

periphery while this button is pressed.

"REW/REV" .............. The pickup slides toward the inner

periphery while this button is pressed.
If PICKUP IN is on, input is invalid.

"PLAY" ..................... Invalid
"STOP" ..................... Return to step 1

*If the focus is not received, the process returns to step 1.

Other cautions
• TOC IL is not available for this test mode.

The tuner test mode is intended to store the adjustment
and measurement frequencies in the preset memory
CH.   When adjusting the tuner section in the production
line, adjusting personnel are not required to set frequency.

Press the "TUNER(BAND)" and "VOLUME UP" buttons
in POWER OFF state and turn on the power by the use
of "ON/STAND BY" button to preset and store frequency
for adjustment and measurement of destination specified
by the AREA terminal in the preset memory CH.  However,
Ordinary 1 and Ordinary 2 are stored in the destinations
when the test mode is obtained.

(As for frequencies to be preset and stored for each
destination, refer to item 3.)
The tuner test mode is started from preset No.1.
The operations of test mode are identical with the ordinary
operations of TUNER function.  FUNCTION switching is
invalid.

It is necessary to discard the content of preset memory
when the tuner test mode is ended; be sure to write "0000"
or "1111" bits in the memory to be checked for judging
memory error at initial setting and to initialize memory.

When the tuner test mode is obtained, the following display
lights for one second.

• The TUNER TEST 2 mode is obtained with  >> + MEMORY/
SET + ON/STAND-BY. ->Turn off AC in the TEST 2 mode
to restore the initial state.

Turn off POWER to protect the memory of TEST 2 mode.
Turn off POWER again to obtain the ordinary operation
while the data is stored in the memory (besides TUNER).

If AC OFF state is maintained in this state for about 1/2 day,
start is executed in the initial state.

• To clear the whole memory, insert the AC cord, pressing
MEMORY/SET + CD PLAY.