Starkey SurfLink Operation Manual page 9

Where P is the maximum output power rating of the transmitter in watts
(W) according to the transmitter manufacturer and d is the recommended
separation distance in meters (m).
Field strengths from fixed RF transmitters, as determined by an
electromagnetic site survey, (a) should be less than the compliance level in
each frequency range, (b).
Interference may occur in the vicinity of equipment marked with the
following symbol:
Note 1: At 80 MHz and 800 MHz, the higher frequency range applies.
Note 2: These guidelines may not apply in all situations. Electromagnetic
propagation is affected by absorption and reflection from structures,
objects and people.
a Field strengths from fixed transmitters, such as base stations for radio
(cellular/cordless) telephones and land mobile radios, amateur radio,
AM and FM radio broadcast and TV broadcast cannot be predicted
theoretically with accuracy. To assess the electromagnetic environment
due to fixed RF transmitters, an electromagnetic site survey should be
considered. If the measured field strength in the location in which the
SurfLink Programmer is used exceeds the applicable RF compliance level
above, the SurfLink Programmer should be observed to verify normal
operation. If abnormal performance is observed, additional measures may
be necessary, such as reorienting or relocating the SurfLink Programmer.
Over the frequency range 150 kHz to 80 MHz, field strengths should be
b
less than 3 V/m.
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Recommended Separation Distances Between Portable
and Mobile RF Communications Equipment and the
SurfLink Programmer
The SurfLink Programmer is intended for use in an electromagnetic
environment in which radiated RF disturbances are controlled. The
customer or the user of the SurfLink Programmer can help prevent
electromagnetic interference by maintaining a minimum distance
between portable and mobile RF communications equipment
(transmitters) and the SurfLink Programmer as recommended below,
according to the maximum output power of the communications
equipment.
Separation Distance According to Frequency
of Transmitter
(in meters)
Rated maximum 150 kHz to
output power of 80 MHz
transmitter W d = 1.2√P
0.01 0.12
0.1 0.38
1 1.2
10 3.8
100 12
For transmitters rated at a maximum output power not listed above, the
recommended separation distance d in meters (m) can be estimated
using the equation applicable to the frequency of the transmitter, where
P is the maximum output power rating of the transmitter
in watts (W) according to the transmitter manufacturer.
Note 1: At 80 MHz and 800 MHz, the higher frequency range applies.
Note 2: These guidelines may not apply in all situations. Electro-
magnetic propagation is affected by absorption and reflection from
structures, objects and people.
80 MHz to 800 MHz to
800 MHz 2.5 GHz
d = 1.2√P d = 2.3√P
0.12 0.23
0.38 0.73
1.2 2.3
3.8 7.3
12 23
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