Power lines emit electromagnetic fields as part of their normal operation.
A power strip is an electronic device that is part of many appliances and machines that work with electricity. Its purpose is to reduce, eliminate or deflect electromagnetic interference (EMI) or radio frequency interference (RFI). Any electrical device can generate an electromagnetic field. Many devices can pick up these fields, creating interference with the radio frequencies used by communications equipment. A power strip will eliminate this interference, allowing a purer signal to be transmitted.
Electronic signals are part of a larger energy field known as the electromagnetic spectrum.
Communication devices such as televisions, telephones, and radios work by converting visual and audible information into electronic signals. These signals are then transmitted to receiving devices, which convert them back into understandable communications. Although in electronic form, these signals are part of a larger energy field known as the electromagnetic spectrum. All electronic devices, including power lines, also emit electromagnetic fields as a result of their normal operation. A strip must be used to separate these incidental electromagnetic signals.
When the first home entertainment and communication devices were introduced, there were generally few other electronic devices in the surrounding environment. In modern times, any location will have multiple electrical devices, including computers, kitchen appliances, and power tools, among others. Any of these machines can create electromagnetic interference. Most nations have regulations that limit the amount of interference a manufactured device can create. An examination of the device will often reveal a notice describing the applicable regulations.
Even a device that is not directly connected to a power line, such as a cell phone, is still connected to an internal battery. However, the signal that reaches the phone is often transmitted over phone lines before reaching a transmission tower. Any of these power sources or lines will generate electromagnetic fields that can create interference. The most common type of power strip is used to prevent interference from the device’s own power connections. Another type avoids interference from external power lines or other devices that may be nearby.
A surge protector is usually a type of electronic component called a capacitor. A capacitor is a passive electronic circuit, built into the device, consisting of conductors separated by an insulator. A surge protection capacitor is designed to allow the desired signal to pass through unhindered while recognizing the interfering signal and interrupting it. It often diverts this interfering signal to the “ground” of the device, where it dissipates harmlessly. When a power strip is not working or is not present, the interference can be detected as visual or auditory static which, if severe enough, can completely interrupt the communication signal.