"Picture this: your mobile phone is lying on your desk, close to the speaker of your computer system. A few seconds before you receive a call or SMS message on your mobile phone, the speaker makes a buzzing noise. Is this clairvoyance of the speaker? No way. Here, the wire to the speaker acts like an antenna that picks up and amplifies the signal it receives from the mobile phone network. This is a typical example of electromagnetic interference between electronic components, and it shows that electromagnetic fields are all around us.

Unwanted electromagnetic interference effects occur when sensitive devices receive electromagnetic radiation that is being emitted - whether intended or not - by other electric or electronic devices such as microwaves, wireless computers, radios and mobile phones. As a result, the affected receiving devices may malfunction or fail, of which the malfunction of pacemakers when in the vicinity of certain electronic devices is a striking, yet detrimental, example."