Bruno REGAL CUB 35, Руководство оператора

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© 2001 BRUNO INDEPENDENT LIVING AIDS, INC.
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FDA EXPLANATION OF DISTANCE CHART
Explanation of Separation Distance Table
To find the minimum recommended separation distance between a medical device and a
transmitter from this table, first locate the value in the top row that is closest to the RF immu-
nity of the medical device. Then follow that column down to the row corresponding to the
rated power of the transmitter. The entry in that cell of the table is the minimum recom-
mended separation distance between that medical device and that transmitter.
The recommended separation distance is approximate. The separation distances were
calculated using the following equation:
d = 18.04
Where P is the peak power of the transmitter in watts (W), E is the immunity of the medical
device in volts per meter (V/m), and d is the recommended separation distance in feet. This
approximation becomes very inaccurate at distances less than the wavelength of the trans-
mitter. Therefore, for low-power sources that are normally hand-held, the minimum recom-
mended separation distance is one foot.
The actual separation distance is affected by antenna efficiency and pattern; multipath reflec-
tions; and absorption of buildings, objects, and people. Multipath reflections could increase
the actual separation distance, and absorption could decrease it.
Each recommended separation distance was calculated assuming a single transmitter. If
multiple sources (e.g. cellular phones) are in use, the actual separation distance should be
increased.
Each recommended separation distance was calculated assuming that the transmitter is
transmitting at the maximum power allowed by the FCC for that type of transmitter. In fact,
the actual transmitted power could be less than the maximum, in which case the separation
distance could be decreased.
Also, each recommended separation distance was calculated assuming that the worst-case
susceptibility of the medical device occurs at the frequency of the particular transmitter of
interest. This may not be the case; if not, the actual separation distance could be decreased.