GB511524A - Improvements in or relating to concentric trunk communication cables - Google Patents

Abstract

511,524. Cables. SIEMENS & HALSKE AKT.-GES. Feb. 18, 1938, No. 5200. Convention date, Feb. 26, 1937. Addition to 490,243. [Class 36] A concentric conductor communication cable, more particularly of the air-space insulation type, has its inner conductor constituted by a single metal band bent into tubular form or by a plurality, preferably two but not more than four, of bands of arcuate cross-section assembled into tubular form, the band or bands being furnished with inwardly directed transverse grooves at widely spaced intervals and the edges of the band or bands, which extend longitudinally of the cable with a large, preferably infinitely large, length of lay, abutting so that the parts of the conductor between the grooves have a smooth surface. The space within the inner conductor may be wholly or partly filled by an insulating strand or cord, or by a bare or insulated wire. The abutting edges of the band or bands may be welded or soldered together continuously or at intervals, Fig. 1 shows a hollow conductor comprising grooved bands 10, 11 held together against lateral displacement by an insulating band winding 13, whilst in the construction shown in Fig. 2 the conductor is formed by a single band, the grooves 14 extending helically so as to prevent the abutting edges of the hand from sliding within one another. Fig. 3 shows a high frequency cable having an inner conductor formed by grooved bands 15, 16 bound together, with their grooves 17 relatively staggered, by a strong band 18 of low-loss insulating material, such as polystyrol. Helical spacing members 19 and a closed band winding 20 of insulating material separate the inner conductor from an outer conductor formed of inwardly grooved metal bands 21, 22, over which are applied a strong metal band winding 24, an insulating band winding 25 and a water-tight jacket 26. The cable may be combined with other coaxial cables and/or ordinary twisted pairs or quads.