AmpliVox 260 - Guidance and manufacturers declaration - electromagnetic immunity (1)

39 MODEL 260 INSTRUCTION FOR USE
Guidance and manufacturer’s declaration – electromagnetic immunity (2)
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 Model 260 Audiometer is
used exceeds the applicable RF compliance level above, the Model 260 Audiometer should be observed to verify
normal operation. If abnormal performance is observed, additional measures may be necessary, such as re-
orienting or relocating the Model 260 Audiometer.
b Over the frequency range 150 kHz to 80 MHz, field strengths should be less than 3 V/m.
Recommended separation distances between portable and mobile RF communications equipment and the Model 260
Audiometer
The Model 260 Audiometer is intended for use in an electromagnetic environment in which radiated RF disturbances are
controlled. The customer or the user of the Model 260 Audiometer can help prevent electromagnetic interference by
maintaining a minimum distance between portable and mobile RF communications equipment (transmitters) and the
Model 260 Audiometer as recommended below, according to the maximum output power of the communications
equipment.
Rated maximum output
power of transmitter
W
Separation distance according to frequency of transmitter
m
150 kHz to 80 MHz
d = 1.2√P
80 MHz to 800 MHz
d = 1.2√P
800 MHz to 2.5 GHz
d = 2.3√P
0.01
0.12
0.12
0.23
0.1
0.38
0.38
0.73
1
1.2
1.2
2.3
10
3.8
3.8
7.3
100
12
12
23
For transmitters rated at a maximum output power not listed above, the recommended separation distance d in
metres (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 80MHz and 800MHz, the separation distance for 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.
NOTE 3 WARNING: Portable RF communications equipment (including peripherals such as antenna cables and
external antennas) should be used no closer than 30cm (12 inches) to any part of the Model 260 audiometer including
cables specified by the manufacturer. Otherwise degradation of the performance of this equipment could result.