A 900 megahertz (MHz) wireless transmitter is a device that sends radio waves in the band of 900 MHz to a dedicated receiver. It can be used for many different applications, including video transmission and wireless Internet. Depending on the type of antenna used with the transmitter and its surroundings, a 900 MHz signal can travel up to 20 miles (32 km). In the United States, there are four channels available on the 900 MHz band.
A wireless transmitter sends electronic information through the air in the form of radio waves. The signal is picked up by a receiver and translated back into the original electronic information, which is then displayed in the relevant medium. Wireless transmitters enable users to send signals through the air; this way, they can avoid cluttering up their homes with wires. A 900 MHz wireless transmitter is a relatively high performance transmitter, suitable for sending signal through walls, but it is generally used for short-distance transmissions within the home.
A 900 MHz wireless transmitter typically operates on 9 volts of power and has a 3- to 3.5-inch antenna (7.5 cm to 9 cm). The transmitter can be used for a variety of home applications but is generally used as part of a home closed circuit television (CCTV) system. A 900 MHz wireless transmitter is usually sold with a receiver, which also has to be set on the 900 MHz frequency in order to receive the transmitter's signals.
There are more powerful transmitters available than a 900 MHz wireless transmitter; for example, some run at 2.4 gigahertz (GHz). More powerful transmitters can give better video or audio quality but will use more power. Alternatively, lower frequency transmitters, such as 434 MHz, are available, and these do not require a special receiver.
One of the most common applications for a 900 MHz wireless transmitter is sending video from a camera to a television, monitor, computer or other display device. Transmitters generally have input jacks for both audio and video signals, suitable for audio and video from many sources, including televisions and video cameras. These are generally found in the form of RCA inputs, and the receiver is normally equipped with RCA output jacks for connection to the output display device. RCA cables are very common, and converters are available that can make the transmitter compatible with other types of input cables.