KINOVA
®
Communication system
User Guide
52
Electromagnetic interference from RF sources
This section describes EMI considerations for the Communication System.
Even though the product complies with all relevant standards, it may still be susceptible to EMI
(electromagnetic interference) from RF sources such as radio and TV transmitters, amateur
radio (ham), two-way radios, and cellular phones to name just a few. In this case, the device will
simply re-initialize and you will be able to continue to use it.
The intensity of the interference is measured in volts per meter (V/m). The product can resist
EMI up to a certain level, which is called the 'immunity level'. The higher the immunity level,
the greater the protection. The current technology is capable of achieving at least a 20 V/m
immunity level, which would provide effective protection from the more common sources of
radiated EMI.
There are a number of sources of relatively intense electromagnetic fields in the environment.
Some of these sources are obvious and easy to avoid. Others are not so apparent and exposure
is unavoidable. However, we believe that by following the guidelines and warnings listed below,
the risk of EMI will be minimized.
The sources of radiated EMI can be broadly classified into three types:
1.
Gripper-held portable transceivers (e.g. transmitters-receivers with the antenna mounted
directly on the transmitting unit, including CB [citizens band], walkie-talkie, security, fire/
police transceivers, cellular phones, and other personal communication devices). Some
cellular phones and similar devices transmit signals while they are switched on, even if they
are not actively being used.
2.
Medium-range mobile transceivers, such as those used in police cars, fire trucks, ambulances
and taxis. These usually have the antenna mounted on the outside of the vehicle.
3.
Long-range transmitters and transceivers, such as commercial broadcast transmitters (radio
and TV broadcast antenna towers) and amateur (ham) radios. Other types of gripper-held
devices, such as cordless phones, laptop computers, AM/FM radios, TV sets, CD players,
cassette players, and small appliances, such as electric shavers and hair dryers are unlikely to
cause EMI problems.
Because EM energy rapidly becomes more intense as one moves closer to the transmitting
antenna (source), the EM fields from gripper-held radio wave sources (transceivers) are of
special concern. It is possible to unintentionally bring high levels of EM energy very close to the
communication system while using these sorts of devices. Therefore, the warnings listed below
are recommended to reduce the effects of possible interference with the system.
Do not operate a gripper-held transceiver (transmitter-receivers), such as CB (citizens
band), or switch on personal communication devices, such as cellular phones, while the device is
turned on.
Be aware of nearby transmitters, such as radio or TV stations, and try to avoid coming close
to them.
Be aware that accessories or components in proximity to the device may make it more
susceptible to EMI.
Report all incidents of unintended shutdown to your local distributor, and take note of the
nearby sources of EMI.
