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EMI WARNING
Electromagnetic Interference (EMI) from Radio Wave Sources
Powered electric chairs may be susceptible to electromagnetic
interference, which is a kind of interfering electromagnetic energy
(EM) emitted from sources such as radio stations, TV stations,
amateur radio (HAM) transmitters, two-way radios and cellular
phones. The interference (from radio wave sources) can cause the
power chairs to release its brakes, move by itself or move in
unintended directions. It can also permanently damage the powered
chair’s control system.
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 talkies”, 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.
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, cassette players and small appliances such as
electric shavers and hair dryers, so far, as we know, are not
likely to cause problems to your Powerchair.
