Sharp md ms 721 w service manual

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MD-MS722/C/W/MS721W Ð 2 Ð Precaution to be taken when replacing and servicing the laser pickup. The following precautions must be observed during servicing to protect your eyesagainst exposure to the laser. Warning of possible eye damage when repairing: If the AC adaptor or batteries are connected when the top houising (disc cover) of the unit is removed, and the PLAY key is pressed, the laser will light up during docus access (2-3 seconds). (Fig. 2-1) During the operation, the laser will lesk from the opening btween the magnetic head and the mechanical chassis (Fig. 2-2). In order to protect your eyes, you most not look at the laser durnd repaor. Before repaoring be sure to disconnect the AC adaptor and remove the batteries. Figure 2-1 Figure 2-2 Magnet Head Lasar Beam Optical Pick-Up Main PWB Disc motor Mechanism Chassis Magnet head Optical pick-up Disc cover SAFETY PRECAUTION FORSERVICE MANUAL (MD-MS722W/MS721W ONLY) Precaution to be taken when replacing and servicing the Laser Pickup. The AEL (Accessible Emission Level) of Laser Power Output for this model is specified to be lower than Class I Require- ments. However, the following precautions must be observed during servicing to protect your eyes against exposure to the laser beam. (1) When the cabinet has been removed, the power is turned on without a compact disc, and the Pickup is on a position outer than the lead-in position, the Laser will light for several seconds to detect a disc. Do not look into the Pickup Lens. (2) The Laser Power Output of the Pickup inside the unit and replacement service parts have already been adjusted prior to shipping. (3) No adjustment to the Laser Power should be attempted when replacing or servicing the Pickup. (4) Under no circumstances look directly into the Pickup Lens at any time. (5) CAUTION - Use of controls or adjustments, or performance of procedures other than those specified herein may result in hazardous radiation exposure. CAUTION This Portable MiniDisc Recorder is classified as a CLASS 1 LASER product. The CLASS 1 LASER PRODUCT label is located on the bottom. Use the portable minidisc recorder only in accordance with the instructions given in this manual and do not attempt to interfere with the interlock switch or make any other adjustment as this may result in exposure to hazardous radiation. Laser Diode Properties Material: GaAIAs Wavelength: 785 nm Pulse time: Read mode; 0.8 mW Continuous Write mode; max. 10 mW 0.5S min. cycle 1.5S Repetition CAUTION - INVISIBLE LASER RADIATION WHEN OPEN AND INTERLOCKS DEFEATED AVOID EXPOSURE TO BEAM .VARNING - OSYNLIG LASERSTRÅLNING NÄR DENNA DEL ÄR ÖPPNAD OCH SPÄRRAR ÄR URKOPPLADE. STRÅLEN ÄR FARLIG.ADVARSEL - USYNLIG LASERSTRÅLING NÅR DEKSEL ÅPNES OG SIKKERHEDSLÅS BRYTES. UNNGÅ EKSPONERING FOR STRÅLEN. VARO! AVATTAESSA JA SUOJALUKITUS OHITETTAESSA OLET ALTTIINA NÄKYMÄTÖN LASERSÄTEILYLLE. ÄLÄ KATSO SÄTEESEN. VARNING - OSYNLIG LASERSTRÅLING NÄR DENNA DEL ÄR ÖPPNAD OCH SPÄRREN ÄR URKOPPLAD. BETRAKTA EJ STRÅLEN. ADVARSEL - USYNLIG LASERSTRÅLING VED ÅBNING NÅR SIKKERHEDSAFBRYDERE ER UDE AF FUNKTION. UNDGÅ UDSETTELSE FOR STRÅLING. (Illustration: MD-MS722W)

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MD-MS722/C/W/MS721W Ð 2 Ð Precaution to be taken when replacing and servicing the laser pickup. The following precautions must be observed during servicing to protect your eyesagainst exposure to the laser. Warning of possible eye damage when repairing: If the AC adaptor or batteries are connected when the top houising (disc cover) of the unit is removed, and the PLAY key is pressed, the laser will light up during docus access (2-3 seconds). (Fig. 2-1) During the operation, the laser will lesk from the opening btween the magnetic head and the mechanical chassis (Fig. 2-2). In order to protect your eyes, you most not look at the laser durnd repaor. Before repaoring be sure to disconnect the AC adaptor and remove the batteries. Figure 2-1 Figure 2-2 Magnet Head Lasar Beam Optical Pick-Up Main PWB Disc motor Mechanism Chassis Magnet head Optical pick-up Disc cover SAFETY PRECAUTION FORSERVICE MANUAL (MD-MS722W/MS721W ONLY) Precaution to be taken when replacing and servicing the Laser Pickup. The AEL (Accessible Emission Level) of Laser Power Output for this model is specified to be lower than Class I Require- ments. However, the following precautions must be observed during servicing to protect your eyes against exposure to the laser beam. (1) When the cabinet has been removed, the power is turned on without a compact disc, and the Pickup is on a position outer than the lead-in position, the Laser will light for several seconds to detect a disc. Do not look into the Pickup Lens. (2) The Laser Power Output of the Pickup inside the unit and replacement service parts have already been adjusted prior to shipping. (3) No adjustment to the Laser Power should be attempted when replacing or servicing the Pickup. (4) Under no circumstances look directly into the Pickup Lens at any time. (5) CAUTION - Use of controls or adjustments, or performance of procedures other than those specified herein may result in hazardous radiation exposure. CAUTION This Portable MiniDisc Recorder is classified as a CLASS 1 LASER product. The CLASS 1 LASER PRODUCT label is located on the bottom. Use the portable minidisc recorder only in accordance with the instructions given in this manual and do not attempt to interfere with the interlock switch or make any other adjustment as this may result in exposure to hazardous radiation. Laser Diode Properties Material: GaAIAs Wavelength: 785 nm Pulse time: Read mode; 0.8 mW Continuous Write mode; max. 10 mW 0.5S min. cycle 1.5S Repetition CAUTION - INVISIBLE LASER RADIATION WHEN OPEN AND INTERLOCKS DEFEATED AVOID EXPOSURE TO BEAM .VARNING - OSYNLIG LASERSTRÅLNING NÄR DENNA DEL ÄR ÖPPNAD OCH SPÄRRAR ÄR URKOPPLADE. STRÅLEN ÄR FARLIG.ADVARSEL - USYNLIG LASERSTRÅLING NÅR DEKSEL ÅPNES OG SIKKERHEDSLÅS BRYTES. UNNGÅ EKSPONERING FOR STRÅLEN. VARO! AVATTAESSA JA SUOJALUKITUS OHITETTAESSA OLET ALTTIINA NÄKYMÄTÖN LASERSÄTEILYLLE. ÄLÄ KATSO SÄTEESEN. VARNING - OSYNLIG LASERSTRÅLING NÄR DENNA DEL ÄR ÖPPNAD OCH SPÄRREN ÄR URKOPPLAD. BETRAKTA EJ STRÅLEN. ADVARSEL - USYNLIG LASERSTRÅLING VED ÅBNING NÅR SIKKERHEDSAFBRYDERE ER UDE AF FUNKTION. UNDGÅ UDSETTELSE FOR STRÅLING. (Illustration: MD-MS722W)

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MD-MS722/C/W/MS721W Ð 3 Ð FOR A COMPLETE DESCRIPTION OF THE OPERATION OF THIS UNIT, PLEASE REFER TO THE OPERATION MANUAL. General Power source:DC 3.6 V (rechargeable lithium-ion (MS722/MS722C)battery x 1) DC 5 V (AC adaptor) AC 120V, 60 Hz DC 3.4V: Battery case (commercially available, "AA" size, alkaline battery x 1) DC 4.5V: Separately available car adaptor, AD-CA20X (for cars with a 12-24V DC negative earth electrical system) Power source:DC 3.6 V (rechargeable lithium-ion (MS722W/MS721W)battery x 1) DC 5 V (AC adaptor) AC 110 - 240V, 50/60 Hz DC 3.4V: Battery case (commercially available, "AA" size, alkaline battery x 1) DC 4.5V: Separately available car adaptor, AD-CA20X (for cars with a 12-24V DC negative earth electrical system) Power consumption:7 W (AC adaptor) (MS722/MS722C) Power consumption:0.15A (AC adaptor) (MS722W/MS721W) Output power:RMS; 20 mW (10 mW + 10mW) (0.2% T.H.D.) Charging time:Approx. 3 hours (When using the AC adaptor included with the unit) Battery life: The continuous recording time is for analogue input when the volume level is set to "VOL 0". The continuous play time shows the value when the volume level is set to "VOL 15". The above values are the standard values when the unit is charged and used at an ambient temperature of 20 oC. The operating time when using alkaline batteries may be different, depending on the type and manufacturer of the batteries, and on the operating temperature. Input sensitivity:Output level: (MS722/MS722C) Output level: (MS722W/ MS721W) Dimensions:Width: 3-7/16" (87.0 mm) Height: 1-1/16" (26.7 mm) Depth: 3-1/4" (81.5 mm) Weight:0.49 lbs. (220 g) with rechargeable battery Input socket:Line/optical digital, microphone (powered by the main unit) Output socket:Headphones (impedance: 19 ohms)/ (MS722/MS722C)remote control unit Output socket:Earphones (impedance: 32 ohms)/ (MS722W/MS721W)remote control unit MiniDisc RecorderType:Portable MiniDisc recorder Signal readout:Non-contact, 3-beam semi-coductor laser pick-up Audio channels:Stereo 2 channels/monaural (long- play mode) 1 channel Frequency response:20 - 20,000 Hz (± 3 dB) Rotation speed:Approx 400 - 900 rpm Error correction:ACIRC (Advanced Cross Interleave Reed-Solomon Code) Coding:ATRAC (Adaptive TRansform Acoustic Coding), 24-bit computed type Recording method:Magnetic modulation overwrite method Sampling frequency:44.1 kHz (32 kHz and 48 kHz signals are converted to 44.1 kHz, and then recorded.) Wow and flutter:Unmeasurable (less than ±0.001% W.peek) SPECIFICATIONS When using the rechargeable battery (fully charged) included with the unit When using one, commerically available, high capacity, "AA" size, alkaline batteries (in the battry case)When using one, commercially available, high capacity, "AA" size batteries with the recharge- able battery (fully charged) Continuous recording: Approx. 8 hoursContinuous recording: Approx. 3 hoursContinuous recording: Approx. 11 hours Continuous play: Approx. 10 hoursContinuous play: Approx. 6 hoursContinuous play: Approx. 16 hours Recording level Reference input level Input impedance MIC H 0.25 mV 10 k ohms MIC L 2.5 mV 10 k ohms LINE 100 mV 20 k ohms Specifications for this model are subject to change without prior notice Headphones Ñ 10 mW + 16 ohms 10 mW LINE 300 mV Ñ 10 kohms (-12dB) Maximum output level Specified output Load impedance Headphones Ñ 10 mW + 32 ohms 10 mW LINE 300 mV Ñ 10 kohms (-12dB) Maximum output level Specified output Load impedance