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The sources of radiated EMI can be broadly classified into three types:
1) Hand-held portable transceivers (transmitters-receivers) with the antenna
mounted directly on the transmitting unit. Examples include: citizens
band (CB) radios, “walkie talkie,” security, fire, and police transceivers,
cellular telephones, and other personal communication devices. **Note:
Some cellular telephones and similar devices transmit signals while they
are ON, even when not 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; and
3) Long-range transmitters and transceivers, such as commercial broadcast
transmitters (radio and TV broadcast antenna towers) and amateur
(HAM) radios.
Note: Other types of hand-held devices, such as cordless phones, laptop
computers, AM/FM radios, TV sets, CD players, and cassette players, and
small appliances, such as electric shavers and hair dryers, so far as we know,
are not likely to cause EMI problems to your powered wheelchair.
Powered Scooter Electromagnetic Interference (EMI)
Because EM energy rapidly becomes more intense as one move closer to the
transmitting antenna (source), the EM fields from Hand-held radio wave sources
(transceivers) are of special concern. It is possible to unintentionally bring high
levels of EM energy very close to the powered scooter’s control system while
using these devices. This can affect powered scooter movement and braking.
Therefore, the warnings listed below are recommended to prevent possible
interference with the control system of the powered scooter.
WARNINGS
Electromagnetic interference (EMI) from sources such as radio and TV stations,
amateur radio (HAM) transmitters, two-way radios, and cellular phones can
affect powered scooter and motorized scooters. Following the warnings listed
below should reduce the chance of unintended brake release or powered
scooter movement, which could result in serious injury.
1) Do not operate hand-held transceivers (transmitters-receivers), such as
citizens band (CB) radios, or turn ON personal communication devices,
such as cellular phones, while the powered scooter is turned ON.
