RigExpert AA-1500 ZOOM
Traps
A
trap is usually a resonant L-C network used in multi-band antennas. By using a
simple one-turn wire coil, a resonant frequency of a trap may be measured.
Example:
A coaxial trap constructed of 5 turns
of TV cable (coil diameter is 6 cm) was
measured.
A one-turn coil (about 10 cm in
diameter) connected to the analyzer
was placed, co-axially, a few
centimeters away from the measured
trap. The SWR chart shows a visible
dip near 17.4 MHz, which is a resonant
frequency of the trap.
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