Title :
A Coaxial Load for Ultra-High-Frequency Calorimeter Wattmeters
Author :
Rambo, William R.
Author_Institution :
Formerly, Radio Research Laboratory, Harvard University, Cambridge, Mass.; now, Airborne Instruments Laboratory, Mineola, New York
Abstract :
A design is described for a broad-band coaxial water load suitable for use in ultra-high-frequency calorimeter wattmeters. The load utilizes a water-filled coaxial line as an attenuating section. The low input impedance of this line is matched to the standard transmission-cable impedance in a broadband matching section using a tapered dielectric composed of titanium dioxide. Several requirements influenced the design: the needs for broadband impedance characteristics, sturdy construction, small physical size, and for the ability to measure low powers quickly, being of prime importance. As a practical illustration, a brief description is given of a unit designed to operate in the 1000- to 3000-megacycle frequency ranges and the 5- to 150-watt power range.
Keywords :
Circuits; Coaxial components; Coolants; Dielectrics; Electric variables measurement; Energy measurement; Impedance; Laboratories; Titanium; Wattmeters;
Journal_Title :
Proceedings of the IRE
DOI :
10.1109/JRPROC.1947.234589
