GB379796A - Improvements in or relating to high frequency electrical transmission lines - Google Patents

Abstract

379,796. High frequency transmission lines. MARCONI'S WIRELESS TELEGRAPH CO., Ltd., Marconi House, Strand, London.-(Assignees of Lindenblad, N. E. ; Port Jefferson, Long Island, New York, U.S.A.) June 25, 1931, No. 18409. Convention date, June 25, 1930. [Class 40 (v).] A high frequency transmission line is suspended or supported by attachment to a suspension device (which need not be insulated) at a point at the middle of a symmetrical loop which is one or an odd plurality of half wave-lengths long. The invention is designed to overcome insulation difficulties with high frequency lines the two conductors of which are closely adjacent to eliminate radiation, and utilizes the fact that a U-shaped conductor one half wave-length in length presents substantially infinite impedance to the working frequency, and its centre or voltage nodal point may be safely earthed without loss. Fig. 1 shows a high frequency input 2 supplying an output circuit 10 over transmission lines 4, 6, 8. Lines 4, 8 are tapped on line 6 at points #/4 distant from short-circuiting strips 12, which are at voltage nodal points and may be secured to supports 24, 20. Line 6 may be supported at intermediate points 42, 421 by similar connections 36, 38, 36<1>, 38<1> with short-circuiting strips 40, 40<1>. Fig. 2 shows a similar method applied to a bent transmission line C, D, the interconnecting conductors 56 being tapped on to lines C, D at points #/4 distant from shortcircuits 46, 48. The lines may then be directly supported at 50, 52. Specifications 308,664, [Class 40 (v), Wireless signalling &c.], and 373,724 are referred to.