UMAX Data Systems Astra 1220U, Service Manual

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Service Manual
Humidity
Changes in humidity tend not to affect the operation of the scanner in obvious ways. In certain extreme
situations, however, the effects cannot be overlooked.
1. In humid regions, the relative humidity may be less than or equal to 85%. If the scanner is not used for a
long time, a moisture-induced film may coat optical surfaces.
2. In dry regions, where the relative humidity may be as low as 30%. static electricity becomes a serious
danger, When disassembling the scanner, be sure you never touch ICs, especially the CCD, without
proper static protection.
Dust
If a scanner is used in a dusty environment, such as a factory, dust could pass through the housing and
contaminate the optical surfaces. It is advised that you wipe the optical surfaces with a cotton swab or soft
cloth that has been saturated with alcohol.
Aging
Some of the effects of aging on the performance of the scanner in are additional noise and lamp failure.
Warning signs of impending lamp failure include a darkening of the tube near the electrodes and low
brightness (lower than 50% of the initial value).
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