Adjustment; Test Mode - Sharp MD-MT20 Service Manual

MD-MT20/20C/20W
Test disc
MD adjustment needs two types of disc, namely recording disc (low reflection disc) and playback-only disc (high
reflection disc).
Type
1 High reflection disc MMD-110 (TEAC Test MD)
2 Low reflection disc
3 Low reflection disc
4 Low reflection disc
Note: Use the low reflection disc on which music has been recorded.
Entering the TEST mode
1. Setting at port (power nonconnected state)
(1) Set the port as follows.
TEST1 : "Low" (TP416)
TEST0 : "High"
(2) Turn the Power ON.
(3) Test Mode STOP [ T E S T _ ]
2. Setting by special button operation (in standby state)
(1) Holding down the DISP button and ENTER button, press the PLAY button.
(2) Normal mode setting initialization (BASS setting, VOL setting, etc.)
*Since the unit is changed to the setting for production line inspection , be sure to set it to the default setting state in the following default
setting procedure before returning it to the user.
(3) Indication of microcomputer version for one second [ 3 1 8 A f X ]
(4) Whole LCD lighting for 2 seconds
(5) Test Mode STOP [ T E S T _ ]
*When the PLAY button is pressed during indication (3) and (4), the process proceeds to (5).
Leaving the TEST mode
(1) Press the STOP button in the TEST mode stop state or version indicating state or whole LCD lighting state.
Shipping setting method
Holding down simultaneously the VOLUME-DOWN Button and PLAY Button of the set unit without disc, supply the power from the DC IN plug.
After the indication "INIT" -> "BYE OK" disappears, release the power supply of DC IN.

Test Mode

1. AUTO 1 Mode • Perform preliminary automatic adjustment.
• If the combination of mechanism and pickup
PWB has been changed, be sure to start from
AUTO1.
2. AUTO 2 Mode • Perform ATT (attenuator) automatic adjustment.
• Perform continuous playback (error rate display,
jump test)
3. TEST-PLAY Mode • Continuous playback from the specified address
is performed.
• 1 line, 10 lines or 384 lines manual jump is
performed.
• C1 error rate display (pit section), ADIP error
rate display (groove section)
• The temperature correction is performed only when
servo start is performed, but the posture correction
is not performed during continuous playback.
4. TEST-REC Mode • Continuous record from the specified address
is performed.
• Change of record laser output(servo gain is also
changed according to laser output).
• The temperature correction is performed only
when servo start is performed, but the posture
correction is not performed during continuous
recording.
5. MANUAL 1 Mode • Temperature is displayed. (Updating in real time)
• Seeing the displayed adjustment value, perform
preliminary manual adjustment.
(Error rate indication, jump test)
6. MANUAL 2 Mode • Temperature is displayed. (Updating in real time)
• Seeing the displayed adjustment value perform
manfully the preliminary adjustment.
(Error rate indication, jump test)
• Continuous playback is performed
(error rate display, jump test).
Test disc
MMD-212 (TEAC Test MD) 74-minute disc
MMD-213A (TEAC Test MD) 80-minute disc
Recording minidisc
Microcomputer version

ADJUSTMENT

88GMMD-110
88GMMD-212
88GMMD-213A
UDSKM0001AFZZ
Destination
EEPROM version
7. RESULT 1 Mode
8. RESULT 2 Mode
9. DIGITAL INPUT Mode
10. ERROR INFORMATION • Error information is displayed.
Mode
11. NORMAL Mode
12. EEPROM Mode
13. INNER Mode
– 12 –
Parts No.
• The value adjusted in AUTO1 or MANUAL1 is
indicated.
• (Execution in servo "OFF" state").
• The value adjusted in AUTO 2 or MANUAL 2 is
indicated.
• Adjustment value is changed manually.
(error rate display, jump test).
• Digital input information is displayed.
• Error information is initialized
• The mode is changed from the TEST mode to
the normal mode without adjustment.
• In the normal mode the internal operation mode,
memory capacity, etc. areindicated.
• In the normal mode both temperature correction
and posture correction are perfomed.
• Factors of digital servo are changed manually.
(Each servo is turned on individually.)
• Cut-off frequency of BASS1, BASS2 and BASS3
is selected manually.
• Temperature detection terminal voltage is
measured, and the reference value is set.
• Defaults are selected and set.
• Setting of EEPROM protect area is updated.
(In case of protect releasing)
• Determine the position where the INNER switch
is turned on. (only high reflection disc).
• The temperature correction is performed only
when servo start is performed, but the posture
correction is not performed.