10. A brief review.
a. Combinations of coils and capacitors are impractical as resonant
circuits above 500 megahertz.
c. Therefore, at microwave frequencies, a resonant cavity is used as a
d. A resonant cavity is a hollow chamber with conducting walls.
e. All energy generated in a resonant cavity is contained within its
f. Resonant cavities have very little resistance and a very high Q.
g. Now that you know the characteristics of a resonant cavity, let's
see how they work.
11. We can best describe the operation of a resonant cavity in terms of
a. Since resonant cavity electron flow is limited to the inside walls,
we will explain the operation of a cavity in terms of fields. We will also
represent the field intensities.
b. Current flow in an antenna creates a magnetic field, called the H
field, that encircles the antenna. The magnetic field produces an electric
field, called the E field, at right angles to itself. This combination of H