أشرف عثمان للإلكترونيات
أهلا وسهلا بكم ونتمنى أن تستفيد معنا


schematic-VIDEO CASSETTE-monitor-service manual SHASSIS Panasonic Philips SAMSUNG SANYO SHARP SONY toshiba Aiwa AKAI DAEWOO Goldstar HYUNDAI VIDEO Grundig Hitachi JVC LG Mitsubishi National NEC ORION VESTEL Corus-Repair-Plasma-LCD
 
الرئيسيةالتسجيلدخول
https://twitter.com/ashraf69osman--- https://www.facebook.com/ashraf.osman.73-- https://plus.google.com/u/0/+ashraf5914

شاطر | 
 

 Portable MiniDisc Players 4-th generation of SONY

استعرض الموضوع السابق استعرض الموضوع التالي اذهب الى الأسفل 
كاتب الموضوعرسالة
MSA
مشرف عام
مشرف عام


عدد المساهمات : 542
تاريخ التسجيل : 16/06/2010

مُساهمةموضوع: Portable MiniDisc Players 4-th generation of SONY   الجمعة أبريل 22, 2011 4:15 pm

Portable MiniDisc Players 4-th generation of SONY




Review of portable MiniDisc player


As you know, MiniDisc player
is a complicated technical device in
which uses modern methods
audio signal processing and the latest
achievements of microelectronics. This contributes to
not only improve the manufacturability, quality and
reliability of the device, but also increases the demands on
professional masters performing repairs
this technique. Modern MiniDisc
Players are highly integrated
systems. The modern technology allows
produce very reliable components that
confirmed by the low percentage of refusals
are associated with defects in components. Weak
places in the apparatus of this kind are
mechanical components and parts subject to wear,
and defects in printed circuit boards. At the same time
high degree of integration allows
minimize the number of ICs, combining
functions that were performed earlier by different
chips. Thus, decreases
number not only chips but also the number
tracks on the circuit board, connecting the various
chip, which increases the reliability of the machine
whole. In addition, improved weight and size
indicators, as well as power consumption. Trend
to the gradual integration of functions that are
performed by different chips into one
chip illustrated in generations
Development MiniDisc players.

So, the first generation of MiniDisc
player, represented by
is the MZ-1 (1992), had about a dozen chips
(See Figure 1)


[ندعوك للتسجيل في المنتدى أو التعريف بنفسك لمعاينة هذه الصورة]


Fig. 1

As seen from the flowcharts each chip in
This player works only one,
maximum of two functions. Compression algorithm on the same ATRAC
engaged simultaneously to two chips
left and right channels separately. To this must be
add that at the time, when released
MiniDisc players Tier
ATRAC compression algorithm is being developed, and he
was far from perfect. Therefore, the quality
record and play back on those
years had significant flaws.

In the second generation of players (see Fig. 2)
compress the data stream has already happened in one
chip CXD2531AR (ATRAC version 2). Typical
Representative of this generation - MZ-R2 (1994). This
player had already ATRAC version 2, which also
fell far short of the required quality.
Players of the second generation were built
on the same chips as the first, for
except for RF-amplifier, ATRAC decoder, DAC / ADC and
Of course, the system controller. Was changed and
optical unit.


[ندعوك للتسجيل في المنتدى أو التعريف بنفسك لمعاينة هذه الصورة]


Fig. 2

Significant reduction in the number of chips
occurred in the third generation MiniDisc
players (see Fig. 3), representative
which are the MZ-R3 and the MZ-B3 (1995). EFM functions and
error-correcting coding, ADIP-demodulator
processor and servo systems are now performed in
single chip CXD2535BR. In addition, ATRAC compression
and impact protection are also made on the same
Chip CXD2536R.


[ندعوك للتسجيل في المنتدى أو التعريف بنفسك لمعاينة هذه الصورة]


Fig. 3

In the fourth generation of players (see Figure 4)
combining both the above chip in an CXD2652R.
The quality of compressed ATRAC-4, which
used in this generation, has been
quite high and comparable to the quality of
recording on CD. A typical representative
this generation of portable players
is the MZ-R30 (1996)


[ندعوك للتسجيل في المنتدى أو التعريف بنفسك لمعاينة هذه الصورة]


Fig. 4

A few years after that all portable
MiniDisc players were built under the scheme
Basic Player MZ-R30. They use the same chips
The same architecture performance. Differences
is to improve ways
constructing a system of supply and location
components. Besides that, I was soft system
processor, which allowed without changing the
apparatus and add a custom service
function. For example, MZ-R55 (1998), built
almost on the same chips as the MZ-R30,
has much smaller dimensions and weight, and
also low power consumption. Increased
memory capacity increases significantly the
duration of impact protection.

Currently there MiniDisc
Players of the fifth generation (see Fig. 5).
The representative - MZ-R90 (1999). It has teamed up
two chips: DSP and RAM.


[ندعوك للتسجيل في المنتدى أو التعريف بنفسك لمعاينة هذه الصورة]


Fig. 5



Overview chips ATRAC, used in
stationary and portable applications.



Version of the algorithm

Name Products

MD Player

Date of start of production.
ATRAC 1 CXD-2527 MDS-101 2/93
ATRAC 2 CXD-2531 MDS-102
MDS-501
11/93
2/94
ATRAC 2 CXD-2531R MDM111
MDH-10
ATRAC 3 CXD-2536R MZ-R3 5/95
ATRAC 3.5 CXD-2536A MDS-JA3ES 6/95
ATRAC 3.5 CXD-2536B MDS-503 10/95
ATRAC 3.5 CXD-2536AR MZ-E40 1/97
ATRAC 4.0 CXD-2650R MDS-JE500/S37
S. Ameriakanskaya model MDS-JE510
MDS-JE700
8/96
ATRAC 4.0 CXD-2652R MZ-R30 8/96
ATRAC 4.0 CXD-2652AR MZ-R50/MZ-R55/MZ-R37
The European model MDS-JE510
8/97
ATRAC 4.5 CXD-2537R MDS-JA50ES 12/96
ATRAC 4.5 CXD-2654R MDS-JE520 9/98
ATRAC Type-R DSP CXD-2656R MDS-JA20ES/JA22ES 5/98



The main differences of MZ-R30 and MZ-R50.


Further, we consider the 4 th player
generation as the most frequently encountered in
service. The base model MZ-R30 is
was described in detail in many sources.
Therefore, we consider such models as the MZ-R50 and MZ-R55 in
compared with the MZ-R30.


Power Supply Types


There are three types of power sources in players
MZ-R30/50/55:


Network adapter

  • Li-Ion battery or
    NiMH

  • External dry battery



    Thus, the processor must perform
    select and connect to a particular scheme
    supply and recharge
    connected battery.


    Differences in the power circuit.


    Power supply in the MZ-R50 slightly simplified for
    compared with the MZ-R30 (see Fig. 6 and 7). In the MZ-R50 a common wire
    all possible sources of power connected
    together, but their connection is provided with
    using MOS transistors arranged in IC808,
    that commute with the positive pole
    sources.


    [ندعوك للتسجيل في المنتدى أو التعريف بنفسك لمعاينة هذه الصورة]


    Fig.6 Scheme of MZ-R50 (battery power)


    [ندعوك للتسجيل في المنتدى أو التعريف بنفسك لمعاينة هذه الصورة]


    Fig.7 Scheme of MZ-R50 (powered by an adapter and
    battery)

    The Player MZ-R30 switching sources
    also occurs on the positive wire, then
    While the common wire is connected together, except
    Lithium-ion battery (see Fig. 8, 9 and 10).

    The positive pole of lithium-ion
    the battery is connected in series
    through P-channel MOS transistor located in the
    IC809 and through one of the N-channel MOS transistors
    located in IC808 (Fig. Cool. While the player
    lithium-ion battery the second transistor,
    located in IC808, the player connects to the circuit
    the negative pole of the battery. During
    charge lithium-ion battery it
    negative pole connected to ground through
    low-resistance resistors R972 and R975, the voltage drop
    which provides information on the current charge. This
    voltage recorded chip IC909,
    which is supported by Q902 rated
    charge current (Fig. 10).


    [ندعوك للتسجيل في المنتدى أو التعريف بنفسك لمعاينة هذه الصورة]


    Fig.8 Phase Power MZ-R30 Li-ion
    Battery

    As for the player MZ-R50, Charging
    supported by transistors Q901 and Q902.
    The current through the transistors is given the value
    parallel-connected resistors R907, R908 and
    should be about 400mA.


    [ندعوك للتسجيل في المنتدى أو التعريف بنفسك لمعاينة هذه الصورة]


    Fig.9 Scheme of power from the MZ-R30
    Ni-MH battery


    [ندعوك للتسجيل في المنتدى أو التعريف بنفسك لمعاينة هذه الصورة]


    Fig.10 Scheme of the MZ-R30 in the mode of charge
    Battery

    In the rest of the circuit Player MZ-R30 and MZ-R50 is
    similar. In the MZ-R50 used DRAM chip with
    increased capacity (16M). Because of this, this
    model has a higher degree of protection against
    external shocks compared to the MZ-R30.


    The main differences of MZ-R55 and MZ-R30/50.


    Power scheme.


    We now consider the differences between the player MZ-R55. That
    Regarding the choice of power source, in this
    player is more simplified compared to
    MZ-R30/50 (see Fig. 11). When connecting the plug
    external adapter opens minus chain
    battery and battery. Plus the withdrawal of all
    sources are always interconnected. During
    charging its negative pole
    connected to ground through transistor Q903 and
    parallel connected low-resistance resistors
    R915, R916. The voltage drop across these resistors
    provides information on current chip IC901 charge.


    [ندعوك للتسجيل في المنتدى أو التعريف بنفسك لمعاينة هذه الصورة]


    Fig.11 Phase Power MZ-R55

    Thus, we can say that in all the MZ-R55
    possible sources of power actually
    connected in parallel. Directly with them
    receives stress 2B, 2,6 B by means of
    transducers, assembled on IC902 and IC903. These
    voltage feed most of the schemes player.
    Each transmitter can be switched off or
    activated by a signal from the system controller.
    In the process of reading and writing on and
    shutdown occurs only IC902, ie Voltage
    2B, and is used when powered by batteries or
    battery for more economical consumption
    energy. Both the transmitter is disabled when
    Player goes into Sleep. Regardless of these
    transducers directly to the source
    supply is connected inverter-limiter
    IC806 and IC807 after the stabilizer at 2.8 V. This
    voltage is used to supply:


    • the system controller IC802



    • inverters IC902 and IC903


    The converter limiter IC806 supports
    output voltage below 3.3 V at any
    supply voltage. Thus, the voltage
    supply 2,8 V is always supplied to the system
    controller and inverters, in whatever mode
    was not the player.

    Increased capacity of memory chips DRAMv
    Player MZ-R55 gives him two advantages. Firstly,
    it provides greater protection from external
    impacts, and secondly, saves energy
    when working player on batteries or a rechargeable battery.
    This is possible due to the fact that some
    time player can play audio from the buffer
    DRAM, rather than from disk. In this case, the processor can
    power off the main consumers
    Energy: Servo, laser, etc. In the
    Battery voltage converter 2B
    collected on IC902, running a cycle of 53 seconds in
    playback mode and 50 seconds in
    record. During one cycle, it is in
    turned on only on 14
    seconds in playback mode and 12.25 seconds in the
    recording mode. However, these figures are typical for
    player who is stationary.
    If the player is subjected to shocks or shock, then
    during ON state increases by
    amount necessary to search for the servo system
    track. This should be taken into account, since in this
    If the energy consumption of battery
    increases significantly.

    Powered microphone amplifier in the MZ-R55
    organized as in previous models.
    When you connect the microphone plug into the jack
    is short to ground contact sensor and
    the inclusion of the stabilizer on the 2,5, collected on IC304.

    Voltage VG required to supply drivers
    in the MZ-R55 turns on the chip IC601, while
    MZ-R30/55eto voltage is generated in the driver itself.


    Servo system.


    We proceed to consider the differences in the circuits
    servo. The first difference concerns
    contact sensors. In previous models, these
    There were five sensors:


    Sensor having a disc in the player.

  • Sensor reflectivity drive
    responds to the presence of holes in a certain
    place on the cartridge drive.

  • The sensor disk protection from record

  • A sensor registers lid opening
    player.

  • Displacement sensor of the optical block to the center
    disc.



  • The player MZ-R55 missing the first two sensors:
    Sensors boot disk and the sensor definition
    the reflection coefficient of the disc. Respectively
    algorithm for the player during the definition of these
    parameters differs from previous
    models. When closing the cover of the player is
    search focus. The search algorithm is as follows (see Fig.
    12).


    [ندعوك للتسجيل في المنتدى أو التعريف بنفسك لمعاينة هذه الصورة]


    Fig. 12
    الرجوع الى أعلى الصفحة اذهب الى الأسفل
    MSA
    مشرف عام
    مشرف عام


    عدد المساهمات : 542
    تاريخ التسجيل : 16/06/2010

    مُساهمةموضوع: رد: Portable MiniDisc Players 4-th generation of SONY   الجمعة أبريل 22, 2011 4:16 pm


  • The laser power and gain
    RF-amplifier is exposed both to work with
    CD-ROM drive, ie with the disc, whose surface
    has high reflectivity. Search
    starts from the top of the lens, ie
    when it is as close to the surface
    disc.

  • If a CD is loaded, the focus will be successfully
    found. In this case, the search focus is over, and
    System Controller will determine the type of disc - CD.

  • If the loaded MD-disc, the focus will not be found, and
    lens is moved to the original top
    position and laser power and the coefficient
    RF-amplifier gain set as for
    with MD-disk. The next time you start searching
    focus.

  • If the loaded MD-disc, the focus will be successfully
    found, and the system controller determines the presence of
    in the MD-CD player.

  • If the focus again will not be found, then the whole
    procedure is repeated again. This whole cycle
    will be repeated 4 times. After that, if the focus
    and will not be found, the device will give the inscription "NO
    DISC ".




  • In fact, the inscription "NO DISC" will appear first.
    Since the system controller registers
    number of turns the spindle-motor, and if the disc
    not loaded, then after exceeding a certain
    speed, the display shows "NO
    DISC ".



    The work of maintaining the nominal
    laser power is similar to MZ-R50, which is used
    the same optical unit - KMS-280A. Main
    its difference from the one used in the MZ-R30
    (KMS-250A), is the presence of the latter conclusion
    RF modulator. At KMS-280A, this conclusion does not,
    respectively, had no need for
    external power supply connection of the modulator.



    With regard to chain tracking and focus
    tracking and speed disk, the player
    MZ-R55 they work much the same as in MZ-R30/50.
    It is only necessary to note that due to the presence
    greater than MZ-R30/50 buffer memory,
    eliminated the need to continuously read
    information from the disk. In MZ-R30/50 read and write cycles
    was 2 seconds (0.5 seconds reading or writing,
    1.5 seconds pass). At the same servo
    never switched off and continued to monitor the
    focus, tracking and speed disk
    even in between, when in fact no
    happened to read or write. As has been
    mentioned above, the MZ-R55 on battery power
    disables the processor supply voltage to 2V
    time, 37-39 seconds. Thus, the disabled
    power driver. As a result, the disc
    stops and reads or writes occur
    out of or in the buffer memory. When powered from the mains
    adapter power-off does not occur, but
    processor still gives a command to shut down
    tracking the focus and tracking, and servo
    tracking speed translates into the so-
    called coarse mode, in which
    supported the frequency of rotation of the disk, but
    Frame Synchronization is not carried out.



    Chain of signal processing.



    Differences in signal processing circuits between all
    players are very small. In particular, all
    players use the same type of RF-amplifier
    - CXA2523, differing only in the letter index (-A
    for the optical block KMS-230A and-AR for the optical
    Block KMS-280A). Also differs only in letter
    index used in iPods, chip DSP -
    CXD2652 (respectively,-A and-AR). IC DAC / ADC
    in fact one and the same: In MZ-R30/50 worth AK4515, and MZ-R55
    - AK4517. The difference between them lies in the fact that
    in the last integrated volume control,
    control processor. In models where
    applied AK4515 volume control - it
    single chip. If the MZ-R30/50 for linear
    outputs and a headphone used different
    chips (a pair of operational amplifiers and LA4800V
    respectively), the MZ-R55, these amplifiers
    integrated with amplifiers for
    headphones into a single chip AN75355A.




    Major faults arising in
    portable MiniDisc players.



    The practice shows that the main
    faults that occur in the portable
    player associated with the optical block
    mechanism for tracking devices, defect
    PCB, the capture mechanism and drive
    mechanical sensors. Optical assembly is
    the most sensitive parts of a portable
    player, because it is precision
    detail.



    Malfunction of the optical unit.



    The main fault, which occurs with
    optical unit as follows: impaired adjustment
    optical system, broken, or modified
    parameters (pollution-related) mechanisms
    Suspension lens, lens contamination
    lens or prism, the depletion of the laser.



    First of all, make sure that
    defect associated with the optical block. It is possible
    guided by the following symptoms.

    The disc is normally read, but you can not record.

  • The disc is read properly, following the
    the disc to become clean (does not appear
    Only the current record, but erased the previous
    tracks).

  • Unstable reading

    Record with a lot of mistakes.

    Hypersensitivity to external shocks




    If the player has one of the
    the above-mentioned defects, it is necessary
    go to the next validation.
    The device is introduced into test mode. After
    This device is translated into a search mode focus.
    The objective lens of this should move up
    and down evenly. Check with
    power meter, laser radiation power.
    It should be depending on the model order
    0.85 mW. In addition, you have not
    Is contaminated optics. After this it is necessary
    transfer apparatus in the mode of the laser for
    record. Power, which should show the device
    should be about 6.8 mW. WARNING! Can not
    keep the laser in the regime of emission of such a large
    power for a long time (over 15s), so
    as this may damage it. And the final
    consists in the fact that the point at FOCUS ERROR
    chip RF-amplifier (pin 34 on chip
    CXA2523R) connects the oscilloscope to the device
    inserted disc, and then he again transferred to the
    Search mode focus. At the same time on the screen
    oscilloscope should be observed a clear
    symmetrical S-curve, after which the device
    Tracking will make the capture and retention focus.



    In the service center may be
    Fixed problems related to pollution
    lens or prism, if it is available.
    If the measurement revealed that the power
    laser radiation in read below
    nominal or visually observed that the lens
    contaminated, it is necessary to clean
    laser unit. When cleaning the lenses need to
    follow these simple requirements.
    Use only the isopropyl alcohol with 100%
    degree of purification. In no case be
    apply any other alcohols and solvents
    as you may receive the deposit or
    microcracks on the surface of plastic lenses,
    result begins to thicken optics.
    Wipe clean with a need for a spiral, starting from the center
    lens to the periphery with a cotton swab.
    Push on the lens when it is necessary so that the
    She went down to a few of his suspension.
    Wipe with a two or three times, each time using
    new tampon. After cleaning, you must again
    check the power of radiation and to make sure that
    She reached the nominal level.



    If the S-curve is obtained by an asymmetric, then
    necessary to change the optical block to a new,
    because it means violation of the alignment
    optics, which in a service center
    can not be corrected.



    After successful completion of such audits,
    if it was still suspected defect
    optical block, further testing can be
    achieved only by replacing optobloka on
    known-good.



    Fault tracking system.



    Symptoms that indicate a fault
    tracking mechanism.

  • When you go to another track, the unit can not
    find the point of beginning playback.

  • Unstable reading and writing. Usually
    manifested either in the initial or on
    peripheral tracks.




  • Usually the problem is with the wear and tear
    engine drive rotation or tracking
    track. When playing a disc must
    observe the RF-signal (pin 3 IC CXA2523R).
    Jitter on the time axis (the so-called
    jitter) indicates the unevenness of the rotation
    spindle motor. In this case, it is necessary
    replaced. Sometimes the problem is related to
    desiccation or insufficient lubrication
    on the worm gear from the engine monitoring
    track of the optical unit. If lubrication
    This site does not eliminate the defect, the motor
    substitute a new one.



    Defect of the PCB.



    Symptoms suggestive of a defect of the PCB,
    can be very diverse and not
    limited below.

    The player is not included.

    No entries from an external source.

    Reacts to the jolting




    Typically, most faults
    related to the PCB, there is at
    because not enough hard mount board in
    places the external connectors. The result is not very
    careful adherence to mate
    jack is broken printed conductor
    coming from the connector. Perhaps even breakage
    some discrete elements located
    on the board in the vicinity of the connector.
    This is especially true for those MiniDisc
    Players like MZ-R55, which is used
    very thin printed circuit board and power supply
    is like on the console board. In any
    If there is any defect of this kind
    recommended to duplicate the printed
    wires running from the connector, with hinged
    conductors.



    Besides the defect in the printed circuit board may be
    associated with microcracks in the vias
    and microcracks in the conductors. Checking
    by tapping and weak
    deformation of the PCB. Localize the
    possible defect by using fast
    local heating or cooling of the PCB
    during its operation. Regularly pays not to be
    respond to these actions. At detection
    board space, where possible defect propaivayutsya
    all vias and legs suspended
    elements.



    Defect capture mechanism and sensors.



    Symptoms suggestive of a defect mechanism
    capture drive and mechanical sensors.

  • Unexpected stop playback or
    record.

  • Hang the unit.

  • Not going to open the lid (you can not extract
    disk).




  • Fault associated with the loading mechanism
    disc occurs mainly due to its deformation.
    It must be remembered that even a slight
    deformation of the loading disk and can lead to
    malfunction of the apparatus. In this case,
    deformed part is changing. In some
    severe cases have to change the whole
    mechanism in the assembly.






    Tips for tuning and repairing.



    Setting power of the laser can be
    take place in a test mode. Fulfill its need
    simultaneously controlling the current through the laser
    a voltmeter connected to the low-resistance
    resistance (about 1Om) in the food chain laser
    and the radiation power with a special
    meter. You must first set
    power required record 6.8 mW, current
    consumption of the laser at the same time should not exceed
    maximum value, which equals
    rated plus 10%. Rated current
    established for each optobloka
    individually and written on its label. If
    still have to establish a current in excess of
    maximum value, then you can try
    lower power rating at 10%, ie to 6,12 MW.
    Again, the current should not exceed the maximum
    values. If the current is still higher than it
    value, we can assume that the laser lost
    emission and optical block replaced by a new one. Not
    should be placed above the current value of this
    even in non-warranty cases, because
    Otherwise, the laser when recording fast
    exhausted and likely damage
    Tracks that have been recorded before. When
    measurement and adjustment of power
    radiation of 6.8 mW laser is turned on, do not leave
    more than 15 seconds. Besides, do not look at
    the lens from a distance of less than 30cm.



    Some problems can be identified simply
    measuring the current consumption of the portable
    player in different modes. For example,
    when playing with power supply from
    AC adapter current consumption is
    approximately 180-200mA, if the player is in
    stationary. If, during the
    playing slightly to hit the player, then
    current short-term should increase once a
    2-3, which indicates that the servo start
    search for the missing track. During recording
    Current input pulses: 1.5 seconds and 180-200mA
    0.5 seconds, 380-400mA (included in the laser mode
    record). Increased power consumption in all
    modes indicates that either the servo
    work is unstable or defective one
    components of the player. In the latter case it is easy
    found at an elevated temperature of his body.



    When you configure the servo is recommended
    automatically set in each
    Paragraph service menu. For the considered
    players, this setting is done by clicking
    pause button when the player is in
    relevant paragraph in the service menu. Manual
    infusion should be used in extreme
    cases, the finding of a
    malfunction.



    When you replace the chip on the thin boards
    For example, such as those used in the MZ-R55,
    should be particularly careful, because
    even a slight overheating of the board leads to its
    deformation and unfit for further
    operation.
    الرجوع الى أعلى الصفحة اذهب الى الأسفل
     
    Portable MiniDisc Players 4-th generation of SONY
    استعرض الموضوع السابق استعرض الموضوع التالي الرجوع الى أعلى الصفحة 
    صفحة 1 من اصل 1

    صلاحيات هذا المنتدى:لاتستطيع الرد على المواضيع في هذا المنتدى
    أشرف عثمان للإلكترونيات :: قسم CD-DVD-MICROWAVE-
    انتقل الى: