GB635364A - Improvements in or relating to couplings or joints between high frequency electromagnetic waveguides and coaxial lines - Google Patents

Abstract

635,364. Wave-guides; attenuators. SPERRY GYROSCOPE CO., Inc. March 24, 1947, No. 7993. Convention date, March 22, 1946. [Class 40 (viii)] In a coupling between a coaxial line and a wave-guide, Fig. 4, the waveguide 10 extends through the outer conductor 15 of the line into proximity with the inner conductor 13, and the mouth of the guide is provided with an apertured conductive diaphragm 16. Fig. 1 shows an attenuator comprising a wave-guide 10 dimensioned below cut-off at the operating frequency coupled to a coaxial line 11. The wave-guide 10 extends through the outer conductor 15 of the line and its end is closed by a metal plate 16 in proximity to the inner conductor 13 of the line. A rectangular slot 17, perpendicular to the inner conductor, is formed in the plate 16, and wall tapers 18 are provided on the outer conductor to avoid abrupt discontinuities. One end 23 of a pick-up loop 29 extends to form a coaxial line with a tube 22 to which the other end is secured. The position of pick-up loop 29 and tube 22, which slides inside the wave-guide 10, is adjusted by a rack-andpinion mechanism secured to an outer tube 24 connected to inner tube 22 by a screw 27. Step transition units 30, 31 connect the coaxial line 22, 23 with a standard coaxial line 37. The enlarged end section of inner conductor 23 slides within the hollow inner conductor of line 37. In the Specification as open to inspection under Sect. 91 the coupling loop may be provided with shorting bars perpendicular to the loop and extending to the outer conductor of the line, so that the loop does not respond to undesired modes which may exist in the guide. This subject-matter does not appear in the Specification as accepted.