The popularity of closed-circuit television (CCTV) has increased in the last few years. It was originally intended for use by governments and businesses, but many home owners are now discovering its benefits. Choosing the right CCTV monitor can make the difference between an effective system and one that fails to deliver. Even the owners of existing systems should consider replacing their old monitors with the latest technology. Buyers have a difficult choice in deciding what type of monitor to get and what features it should have, so it helps to know a little more about them.
CCTV systems are used mostly for surveillance, crowd control, and theft protection. Even the presence of a camera can be enough to deter someone from committing a crime. In many cities around the world, there is a camera on just about every street corner. Many businesses use them to monitor their property and workforce, and most retail shops have at least one camera watching their customers. A CCTV monitor and camera can also be used at home to identify visitors before opening the front door or gate to them.
Until recently, almost every CCTV monitor in use was a cathode ray tube (CRT). These monitors were bulky, heavy, and created a lot of heat. Their small, low resolution screen also made it difficult to see important details, like facial features and number places. While they are still available today, they are being rapidly replaced by liquid crystal displays (LCD). An LCD monitor is thinner, lighter, and has a higher resolution that shows greater detail. Many systems need to show the views from several cameras at the same time, something which a large LCD monitor is ideally suited for.
When choosing a new CCTV monitor, there are several features that need to be considered. A large screen size and resolution are essential for seeing details. A color monitor is better for identifying clothing and other items. Almost all monitors sold today are color but some cheap security systems have a black and white monitor. The back of the monitor should have input ports that will accept the cables from the cameras or multiplexer. Also, the controls to adjust the brightness and contrast should be easy to reach.
Before buying a CCTV monitor, it is important to check that is supports the same video format used by the cameras. This will either be PAL or NTSC, depending on where the cameras were sold. Some monitors can be switched between the two formats but other are factory fixed and cannot be changed. A monitor that has speakers should be used for cameras that have a microphone. Another thing to check for is the location of mounting holes and whether the monitor will need support brackets.
A CCTV monitor is as simple to setup and use as a television. In a basic system, the signal cable from the camera is plugged directly to the back of the monitor. Many systems have a tape recorder between the camera and monitor to save the video footage so that it can be reviewed at a later time. Systems with a large number of cameras often use a multiplexer to combine all the cameras signals into one output signal. In this case, the monitor is connected to the output of the multiplexer, not the cameras.
Another option is to do away with the CCTV monitor entirely by using network cameras. Instead of being connected to a monitor or recorder with video cables, these cameras are connected to a computer network with Ethernet cables. The cameras are assigned a unique address and treated like any other device on the network. With special software, any computer on the network can be used to view and record the digital video from the cameras. The video can even be sent through the internet to a mobile phone or laptop computer.