Yamaha CRX-E500, Руководство по обслуживанию

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CDC-E500
CDC-E500
3
VARO!: AVATTAESSA JA SUOJALUKITUS OHITETTAESSA OLET ALTTIINA NÄKYMÄTTÖMÄLLE LASER-
SÄTEILYLLE. ÄLÄ KATSO SÄTEESEEN.
VARNING!: OSYNLIG LASERSTRÅLNING NÄR DENNA DEL ÄR ÖPPNAD OCH SPÄRREN ÄR URKOPPLAD.
BETRAKTA EJ STRÅLEN.
■
PREVENTION OF ELECTRO STATIC DISCHARGE
Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components commonly are called
Electrostatically Sensitive (ES) Devices. Examples of typical ES devices are integrated circuits and some field-effect transistors and
semiconductor “chip” components. The following techniques should be used to help reduce the incidence of component damage caused by
electro static discharge (ESD).
1. Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off any ESD on your body by
touching a known earth ground. Alternatively, obtain and wear a commercially available discharging ESD wrist strap, which should be
removed for potential shock reasons prior to applying power to the unit under test.
2. After removing an electrical assembly equipped with ES devices, place the assembly on a conductive surface such as aluminum foil, to
prevent electrostatic charge buildup or exposure of the assembly.
3. Use only a grounded-tip soldering iron to solder or unsolder ES devices.
4. Use only an anti-static solder removal device. Some solder removal devices not classified as “anti-static (ESD protected)” can generate
electrical charge sufficient to damage ES devices.
5. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ES devices.
6. Do not remove a replacement ES device from its protective package until immediately before you are ready to install it. (Most
replacement ES devices are packaged with leads electrically shorted together by conductive foam, aluminum foil or comparable
conductive material).
7. Immediately before removing the protective material from the leads of a replacement ES divice, touch the protective material to the
chassis or circuit assembly into which the device will be installed.
CAUTION: Be sure no power is applied to the chassis or circuit, and observe all other safety precautions.
8. Minimize bodily motions when handling unpackaged replacement ES devices. (Otherwise harmless motion such as the brushing
together of your clothes fabric or the lifting of your foot from a carpeted floor can generate static electricity (ESD) sufficient to damage an
ES device).
Grounding for electrostatic breakdown prevention
1. Human body grounding.
Use the anti static wrist strap to discharge the static electricity
from your body.
2. Work table grounding.
Put a conductive material (sheet) or steel sheet on the area
where the optical pickup is placed and ground the sheet.
Caution:
The static electricity of your clothes will not be grounded
through the wrist strap. So take care not to let your clothes
touch the optical pickup.
1M
Ω
Conductive material
(sheet) or steel sheet
Anti-static wrist strip
PROTECTION OF EYES FROM LASER BEAM DURING SERVICING
This set employs a laser. Therefore, be sure to carefully
follow the instructions below when servicing.
1. Laser Diode Properties
• Material : GaAlAs
• Wavelength : 780 nm
• Emission Duration : Continuous
• Laser Output : max. 44.6
µ
W*
* This output is the value measured at a distance of about 200 mm from the objective lens surface on the Optical Pick-up
Block.
2. When checking the laser diode emission, keep your eyes more than 30 cm away from the objective lens.