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Video systems have many applications, from surveillance to broadcast television. Cabling for video can be specialized or operated over cabling designed for other uses. How well do you understand video cabling? Correct answers and explanations are in red.
1. Video signals can be sent over ________ cables.
A. Coax
B. Unshielded twisted pair
C. Fiber optic
D. All of the above
Video can be sent over any cable with the proper equipment.
2. Video signals transmitted over cable can be either analog or digital.
True
False
All these cables will transmit either analog or digital signals.
3. Traditionally, video has used ________ cable for its higher bandwidth and shielding.
A. Coax
B. Unshielded twisted pair
C. Shielded twisted pair
D. Fiber optic
Coax has been the traditional cable for video because it has higher bandwidth and produces less signal distortion.
4. In order to convert video over coax to UTP cables or vice versa, you need a device called a ________.
A. Media converter
B. Balun
C. Reflector
D. Connector
A balun converts signals from an unbalanced cable (coax) to a balanced cable (UTP.)
5. In order to convert video over coax to fiber optic cables or vice versa, you need a device called a ________.
A. Media converter
B. Balun
C. Reflector
D. Connector
Media converters convert any copper cable systems to fiber optics.
6. Low power cameras can be powered over UTP cabling using power over Ethernet (POE).
True
False
Power over Ethernet can now deliver up to 25 watts of power for devices connected to the cable.
7. Surveillance cameras in a metropolitan area are most likely connected over ________ cables.
A. Coax
B. Unshielded twisted pair
C. Shielded twisted pair
D. Fiber optic
The distances involved in metropolitan systems means that fiber is the only logical choice.
8. If the camera is further than a few hundred meters from the monitoring location, ________ cable is probably the best solution.
A. Coax
B. Unshielded twisted pair
C. Shielded twisted pair
D. Fiber optic
Even after a few hundred meters, fiber is better because it does not require midspan repeaters.
9. If numerous cameras are being multiplexed over a single cable, ________ is probably the best choice.
A. Coax
B. Unshielded twisted pair
C. Shielded twisted pair
D. Fiber optics
Fiber offers much more bandwidth, allowing manycameras to be multiplexed on one fiber.
10. If you are using UTP cable for video, the longest possible length of the cable that can be used will depend on the ________ of the cable.
A. Resistance
B. Reflectance
C. Impedance
D. Bandwidth
The bandwidth of UTP cable determines the length of the cable that can be used for video, so choosing the highest grade (category) is recommended.
HAYES is a VDV writer and educator and the president of The Fiber Optic Association. Find him at www.jimhayes.com.
About The Author
HAYES is a VDV writer and educator and the president of the Fiber Optic Association. Find him at www.JimHayes.com.