Ultra-high-frequency switches and filters

The paper discusses the uses of filters and switches in u.h.f. radiorelay links. Typical requirements for such components are given and possible designs reviewed. As examples, designs of filters and switches used in the London-Birmingham television radio-relay link are given in detail. The switch employs resonant stub-lines placed in shunt with the main transmission lines; typical performance details are given. The filters are of the band-rejection type, and consist of stub lines, composed of a series of nominal quarter-wavelength sections of line, shunted across the main transmission line. Design curves for the filter stubs and complete filters are given. Typical filter-attenuation curves are shown, and comparison between the theoretical and experimental results is made.