GB829485A - Standing wave indicator - Google Patents

Abstract

829,485. Probe circuits for standing-wave indicators. BIRD ELECTRONIC CORPORATION. Feb. 24, 1956 [Feb. 24, 1955], No. 5928/56. Class 40 (8). A pick-up unit for extracting energy propagated along a line comprises a hollow open-ended body 31 divided into two chambers by a perforated partition 49 the components of the pick-up circuit (shown in Fig. 12) being disposed some in each chamber. The pick-up loop 76 is wound on an insulating former 77 which is mounted together with resistor 58 on a conductive plate 42. The upper end of the resistor rests in a metal cup 85 whilst the lower end is connected to the pick-up loop and to a deformable metal plate 96 which provides a variable capacitance between the loop and the inner conductor 10 of the line. The distributed capacitance of the resistor may be varied by means of a sliding metal sleeve 91. The other end of the pick-up loop is connected to one electrode of an annular capacitor 62 whose other electrode is soldered to the plate 42. Connection between the loop and rectifier 64 is provided by a conductor 75 which passes through central apertures in capacitors 61, 62. The body of the rectifier is located in a bore of the partition 49 and is soldered at its lower end to an electrode of the capacitor 61 the other electrode being soldered to the plate 42. Resistor 56 is located in the upper chamber and is supported from an insulated post (not shown) by one of its leads 55. The body of the rectifier is also connected to this post by a conductor 101. The other lead of the resistor 56 is soldered to a tag 104 on an elongated conductive member 41, Fig. 9, mounted between insulating members 39, 43. The member 41 has contact ears 106, 107 which extend into apertures 108 of the pick-up body 31. When the pick-up is mounted on the line it may be rotated through 180 degrees between two positions in which one of the ears 106, 107 is engaged by a spring contact 131, Fig. 3. In each position the pick-up is responsive to energy flowing in one directon only. The spring contact is connected to the central pole 134 of a disc capacitor 122 whose peripheral electrode is connected to the casing. The capacitor is mounted in a coaxial connecting member 118 to which a galvanometer cable is attached. The pick-up is mounted in a socket S where it is held in position by a spring actuated latch 148. The pick-up may constitute the plug of a plug and socket combination such as is described in Specification 764,597. Specification 829,486 also is referred to.