3.0—Home Security and Surveillance Systems

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Chapter
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Video surveillance systems for both home and commercial business use are referred
to as closed circuit TV (CCTV) systems. The name is derived from the type of the system
used for transmission over a closed circuit or private transmission circuit rather
than a standard television broadcast system. CCTV is also used in a wide variety of
applications for schools, business video conferencing, retail store surveillance, and
gambling casinos.
Switchers
Switchers are devices used with multiple camera systems. Although primarily
used in commercial building security and surveillance systems, they can be
scaled to fit the needs of a home security system. They enable several cameras
to be used with a single monitor. The switcher can be programmed to
cycle through all the cameras in a surveillance system or dwell on each camera
for a specified length of time, usually in the range of 1–60 seconds.
Exterior sensors can detect movement and cause cameras to start recording
the image on a VCR.
Quads are special devices that enable the viewer to simultaneously record
and monitor four cameras. It does this by splitting your screen into four sections.
The normal configuration for connecting a quad switcher with a sensor
and a VCR is shown in Figure 3.6, which illustrates the connections
between a quad, a monitor, and four surveillance cameras. The monitor can
view all four images at the same time.
Video Monitor Sensor
Video Cameras
VCR
Figure 3.6 Quad camera switcher.