Figure 8-3.--Simplified block diagram of a commercial television.

Pickup Unit

A block diagram of a standard home television

system is shown in figure 8-3. There are three main

A pickup unit, generally referred to as the camera,

divisions in the diagram. The top division represents

starts the sequence of events that occurs in the CCTV

the video or picture section of the transmitter. The

system. A lens in the camera focuses an image on a

central division represents the audio or sound section

photosensitive (light-sensitive) tube. The type of lens

of the transmitter. The lower division represents the

is determined by the size of the scene to be televised.

television receiver.

It maybe a normal, wide-angle, or telephoto lens. The

size of the camera unit varies from small palm size

mobile units to large units mounted on special

SYSTEM COMPONENTS

platforms. One or more cameras may be connected

into the system to receive the desired picture (video)

A CCTV system consists of three basic units.

and route it as an electronic signal to a control unit

These basic units are the camera(s), or pickup unit(s),

the control unit, and the monitor(s) (fig. 8-4).

Figure 8-3.--Simplified block diagram of a commercial television.

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