ComSonics CyberTek QUALIFIER, User Manual

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Appendix - Qualifier System
3-10
Appendix G: Home Qualification System
Generalized Theory of Operation
Exhibit A
A cable television system distributes signals by a cable suspended on utility poles or by a
cable buried in the ground. A combination of both methods is not uncommon. From the
main distribution cable, a device called a local tap is used to interface the distribution system
cable to the subscriber. From one to eight and possibly more subscribers may be served from
a single local tap location. A multitude of local taps is used through out the distribution
system to provide cable services to subscribers.
From the local tap, in overhead systems, a drop cable is suspended from the local tap at a
safe distance from the ground and secured to the home. The drop cable is routed down the
side of the home to a device called a ground block. The ground block is a pass through
device connected to an earth ground. It is used to prevent static build up between the cable
system and the electrical power wiring of the home. The ground block reduces the risk of
electrical damage to devices within the home connected to the cable system.
The cable enters the home and routes to the device/s within the home. The cable within the
home may be split (branched) into a multitude of paths supplying cable services to many
locations within the home. Examples of devices connected to the internal cabling are
television sets, VCRs, cable modems, digital carrier receivers, and special service
transceivers.
Typical CATV overhead routing to private home.
Drop Cable
Ground Block
Private Home
CATV Distribution System
Local Tap
Upstream Path
Downstream Path