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easily constructed than the conventional sort.
The lower the loss resistance of the wire the higher the dynamic
resistance across the open ends; and to match lower impedances all
that is necessary is to tap it down, just as if it were any other sort of
tuned circuit.
If the line is made slightly shorter than λ/4 the open end behaves as
an inductor and can be tuned by connecting a variable capacitor
across it. Fig. 16.10a is an example of a conventional tuning circuit,
such as might be used in a receiver, and b is the coaxial equivalent. A
coaxial feeder is also used to connect the antenna, and being normally
about 80Ω it is tapped low down ...