4.2
4.2.1
A SECOND AND SEPARATE CABLE TELEVISION NETWORK (SCENARIO 2)
General Description
Scenario 2 foresees that the cable television network would be owned and run by a company other than that which provides the franchised telecommunications services. In evaluating the second network a major question is how much additional ductwork would be required, and the degree of disruption that the duct and cable laying activities would cause. A cable television system in Hong Kong, in order to be successful against both financial and social criteria, needs to reach the maximum feasible number of households. Cable must therefore be laid to pass virtually all residential buildings and houses. Some areas will never be economic for cable television, such as isolated houses in rural areas, small communities on outlying islands. Other areas are currently uneconomic, but are expected to become economic to serve in due course; examples are areas where substantial new building is planned, or where current housing stock is due for wholesale replacement within a few years. The economics of cable television provision in Hong Kong, combined with the high housing densities, are such that the two main cable licence bidders regard it as economic to pass almost all households after five years. It must be realized, however, that a true 100% coverage would only be achieved if a public service obligation to that effect were placed upon the cable television network operator.
Cable can be strung from poles, directly buried in the ground, or laid in ducts (normally semirigid circular-section PVC pipe of 90 or 107 mm external diameter). Pole hung cable is only considered feasible where pole routes already exist (for telecommunication and/or electric power services) and where local environmental considerations do not dictate underground construction. In Hong Kong, underground construction is assumed throughout the urban areas. Directly buried cable is most suitable for providing service to individual households in suburban or semi-rural areas where the cable is to be laid through soft ground. Directly buried cable is more vulnerable than ducted cable to subsequent excavation damage, and once damaged it is difficult to recover, the only solution being to lay a new length in parallel. Where a single cable coming in from the street serves multiple households, continuity of service, maintenance and future flexibility considerations all indicate the ducted approach to be optimum.
4.2.2 The construction of ducts
In the following section BAH examines
the amount of duct required, where it needs to be laid, and associated street works (joint boxes, roadside cabinets etc.)
the possibility of television cables sharing duct space with other pre-existing services.
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