Figure 3-8.
Three-conductor plug,
Figure 3-9. Male and female jacks
male
c. There are several types of video cables and a variety of different plugs.
The most common video cable is called coaxial cable.
Coaxial cable has a hot
conductor which is solid copper wire in the center of the cable. The ground is a
mesh of wires encircling the copper wire. There is an insulating material between
the hot wire and the ground. The ground itself acts as a shield against extraneous
signals.
d. Every coaxial cable has a certain impedance. It will resist the flow of a
signal along it to a certain degree and thus, in reverse logic, will maintain a
certain signal strength as that signal is conducted along it.
The impedance is
determined by the construction of the cable, the thickness of the hot conductor and
ground, and the distance between the inner core conductor and the outer ground. In
essence, impedance is the resistance to signal flow along a given length of cable.
The following cautions should be observed:
(1) Do not bend, knot, twist or step on your cables.
(2) Never tug on the cable itself.
Always insert and remove them from the
receptacles by gripping the jack.
58
Previous Page
