User's Manual

SD5/SD6 Ultrasonic TableTop Doppler User Manual EMC Information

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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 SD5/SD6 is used exceeds the applicable RF compliance level

above, the SD5/SD6 should be observed to verify normal operation. If abnormal performance is

observed, additional measures may be necessary, such as reorienting or relocating the SD5/SD6

Over the frequency range 150 kHz to 80 MHz, field strengths should be less than 3 V/m.

A2.4 Recommended Separation Distances

Recommended separation distances between portable and mobile RF communications

equipment and the SD5/SD6

The SD5/SD6 is intended for use in an electromagnetic environment in which radiated RF

disturbances are controlled. The customer or the user of the SD5/SD6 can help prevent

electromagnetic interference by maintaining a minimum distance between portable and mobile RF

communications equipment (transmitters) and the SD5/SD6 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

(d=35

1.995 MHz to 2.010 MHz

2.985 MHz to 3.015 MHz)

80 MHz to 800 MHz

D=1.2

800 MHz to 2.5 GHz

D=2.3

0.01 0.12(3.5) 0.12 0.23

0.1 0.38(11.1) 0.38 0.73

1 1.2(35) 1.2 2.3

10 3.8(111) 3.8 7.3

100 12(350) 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 80 MHz and 800 MHz, 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.