Improvements in or relating to apparatus for measuring high frequency power

Abstract

Abstract 614,005. Wave-guides. SPERRY GYROSCOPE CO., Inc. Feb. 28, 1946, No. 6298. Convention date, Feb. 28, 1945. [Class 40 (viii)] [Also in Group XXXVI] High-frequency power is transferred from a two-conductor transmission line to a waveguide or similar load over a loop comprising a temperature - responsive resistance and is measured by measuring the thermal response of the resistance. A coaxial line 18, 19, Fig. 2, feeds oscillations from an oscillator to an attenuator 21 over an inductive loop 48 which includes a current variable resistance 40; the resistance 40 is connected over conductors 19, 42 in a bridge circuit, Fig. 3, which is fed with D.C. and balanced by adjustment of resistance 62 before and during the application of high frequency to the element 40, the difference in the readings of a milliameter 63 being related to the high-frequency power supplied. Attenuator.-The attenuator 16, Fig. 1, comprises a wave-guide dimensioned to operate below cut-off; a cylindrical section 16 has its length determined by a plug of dielectric material 26, Fig. 2, having a terminating resistor 92; the plug is adjustable along tube 16 by rack and pinion 30, 31, Fig. 1. A wave-guide 34 initially cylindrical, but terminating as a rectangle 14 connects the attenuator to the load. Inductive loop.-The coaxial line 18, 19 is coupled to the wave-guide 21 by a first quarterwave transmission line 48, 49, Fig. 4, shortcircuited at 18 and a second quarter-wave transmission line 48, 42<1> which transforms the high impedance between the lower ends of 42<1> and 48 into a low impedance between 44 and 46, thus providing a return path for the high frequency in resistance 40 while maintaining insulation against direct current between resistance 40, and conductor 18.

Inventors

No inventors recorded.

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