標準號：IS 5026-1987
發布日期：1988/12/1 12:00:00
實施日期：1999/12/31 12:00:00
適用范圍：1.1 This standard covers flexible and semi-rigid radio frequency cables with solid and semi-solid dielectric cores, with single, dual and twin inner conductors, primarily intended for use as transmission lines to conduct energy in a simple power transfer continuously or intermittently.Note — In general, these cables are designed for low-loss, stable operation from the relatively low frequencies through the higher frequencies in the microwave and radar regions of the frequency spectrum. These cables are mainly used as connections to equipment or systems and for their inter-connection cables may also be used as circuit elements, delay lines or impedance matching devices.1.1.1 Cable Types1.1.1.1 Flexible, coaxial single conductor — A flexible coaxial cable is constructed of a single inner conductor covered by a flexible low-loss RF dielectric core material which is then surrounded by a braided outer conductors, with thewhole covered by a protective covering. In some cases, this is covered by an extra braided armour for use in extremely abusive applications. Each element of the cable is designed to contribute to the requirements of the finished product.1.1.1.2 Semi-rigid, coaxial single conductor — Semi-rigid coaxial cables are constructed of a single inner conductor covered by a flexible lowloss RF dielectric core material, which is then surrounded by a solid, continuous, metallic outer conductor.1.1.1.3 Two-conductor — Individual dielectric cores of two-conductor cables shall meet the requirements of solid or semi-solid dielectric cores. One strand of one of the inner conductors shall be coded for identification and shall be visible without disturbing the stranding. That is, if all the strands of the innner conductors are coated, then one strand shall be bare; or if all of the strands are bare, then one strand shall be coated.a) Twin — Twin cables shall be constructed of individual inner conductors within individual dielectric cores, within a common outer conductor or may have individual inner conductors within a common outer core that may be filled-to-round.b) Dual — A dual cable shall be constructed of individual coaxial cables enclosed within a common outer conductor.1.1.1.4 Triaxial — Triaxial cables are constructed the same way as regular coaxial cables except for an additional interlayer of dielectric material over the outer conductor, over which is laid an extra shield, with the whole covered by a protective covering.