Multi Camera CCTV System ?
Most systems today comprise of more than one camera , but you don't need a monitor and recorder for each camera ; several cameras can share one monitor and hard disc recorder .
Equipment is available that will split the monitor into four separate screens displaying four cameras , or a four way sequence unit can be used which allows you to choose which camerayou would like to view. Alternatively, the automatic mode it will sequence through the four cameras that are connected.
However, the most common way of controlling multiple cameras is via a multiplexer .
To keep it simple, a multiplexer incorporates the above facilities but also has the ability to individually code mark each image from each camera and because of this, a multiplexerallows all of the cameras on a system to be recorded onto one tape or hard drive unit. The multiplexer then uses these code marks to play back the recorded picture from thecamera that you wish to view.
Historically multiplexers and recording units were separate pieces of equipment, but over recent years manufacturers have developed units that do both jobs.