Improvements relating to impedance transformers having high, adjustable, transformation ratios, suitable for use over a wide band in the hyperfrequency range

摘要

658,581. Impedance transformers. WALLAUSCHEK, R. June 7, 1949, No. 15198. Convention date, June 16, 1948. [Class 40 (viii)] An impedance transformer comprises a transmission line, whose length approximates to a quarter wavelength in the working band, connected in series with an adjustable capacity between the impedances to be matched and having adjustable shunt capacities at each end. In the construction shown, two coaxial lines B and C are to be matched. The matching section E is directly connected to line B and is connected to line C through a capacity varied by sliding an end piece D on the latter. Screws M and N form variable shunt capacities at each end of line E. The inner sections of these coaxial lines are supported by dielectric beads F and G. In an alternative construction the shunt capacities may be created by coaxial stub lines of length greater than one quarter wavelength connected in parallel at each end of conductor E, and having a tuning piston each.