BLUE CHIP Alpha Touch Computer, Руководство пользователя

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Alpha Panel Mount Precautions
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Any metal back plate must be securely screwed to the chassis of the computer to ensure good metal-to-
metal (i.e. earth) contact.
Metal, screened, connector bodies should be securely connected to the enclosure.
The external cabling to boards causes most EMC problems. It is recommended that any external
cabling to the board be totally screened, and that the screen of the cable connects to the metal end
bracket of the board or the enclosure and hence to earth. Round, screened cables with a braided wire
screen are used in preference to those with a foil screen and drain wire. Wherever possible, use metal
connector shells that connect around the full circumference of the cable screen: they are far superior to
those that earth the screen by a simple “pig-tail”.
The keyboard and mouse will play an important part in the compatibility of the processor card since
they are ports into the board. Similarly, they will affect the compatibility of the complete system. Fully
compatible peripherals must be used otherwise the complete system could be degraded. They may
radiate or behave as if keys/buttons are pressed when subject to interference. Under these
circumstances it may be beneficial to add a ferrite clamp on the leads as close as possible to the
connector. A suitable type is the Chomerics type H8FE-1004-AS.
USB cables should be high quality screened types.
Ensure that the screens of any external cables are bonded to a good RF earth at the remote end of the
cable.
Failure to observe these recommendations may invalidate the EMC compliance