AmpliVox 270+ - 8. APPENDIX A - FREE FIELD CALIBRATION PROCEDURE; General Calibration Overview and Assurance

51
D-0126050 rev 1 - 270+ Operating Manual
Guidance and manufacturer’s declaration – electromagnetic immunity (2)
Recommended separation distances between portable and mobile RF communications equipment and
the Model 270+ Audiometer
The Model 270+ Audiometer is intended for use in an electromagnetic environment in which radiated RF
disturbances are controlled. The customer or the user of the Model 270+ Audiometer can help prevent
electromagnetic interference by maintaining a minimum distance between portable and mobile RF
communications equipment (transmitters) and the Model 270+ 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 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 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.