A 5.8 GHz wireless audio video signal is used by devices commonly known as video senders. These are used when somebody wants to watch the video and audio from a device in one location on a TV set in another location without cabling. In theory, such devices can carry a signal up to 300 feet, though in practice this depends on the thickness and material of intervening walls and floors.
There are two parts to a device that carries a 5.8 GHz wireless audio video signal: the transmitter, which attaches to the source device such as a cable box in a living room; and the receiver, which attaches to the viewing device, such as a TV set in a bedroom. Both devices look very similar, which can cause confusion during set-up if they are not labeled clearly. The devices carry two cables, or sets of cables: a power lead and an audio-video cable or cables that connects to the source device or viewing device. With some set-ups, the transmitter will also have a set of cables that connect to the TV set by the source device, passing the signal through. This will be needed if the source device only has one set of audio-video outputs.
A device carrying a 5.8 GHz wireless audio video signal may have some other features. The most prominent is a remote control extender. This involves a sensor on the receiver being able to pick up a remote control signal and then pass it on to the audio or video device being controlled.
There are two ways the redirected remote signal can reach the sensor of the device. One is for the transmitter unit of the video sender to beam it directly. This can be clumsy, as it means the device must be placed in front of the TV rather than hidden away. The second way is through what is sometimes called an IR mouse. This is a tiny device that is attached in front of the sensor and then connected to the transmitter by a wire.
There are some potential drawbacks to devices that use a 5.8 GHz wireless audio video signal. The biggest is that some cordless phones also use the 5.8 GHz frequency, creating the risk of interference. To get around this, most audio-video sender devices allow the user to select one of several broadcast channels within the frequency. Both the transmitter and receiver need to be set to the same channel, which can be the explanation for some apparent technical faults.