There
is presented 3- Element Arrow Directional antenna for the 145-
MHz Band. The antenna is matched with coaxial cable with help
of gamma- matching. Antenna has good SWR at the band and excellent
F/B ratio. Antenna does not require follow to strictly dimension
of the elements. So the antenna may be done ever by a ham who
has no large experience in the antenna building.
Antenna
has 50- Ohm input impedance (at gamma match) that allows feed
the antenna directly by 50- Ohm coaxial cable. Figure 1 shows schematic of the antenna. Figure 2
shows design of the gamma- match for the antenna. Antenna reflector
antenna made of tube/rod in diameter 8- mm. All others antenna
elements of the antenna made of tube/rod in diameter 8- mm. Gamma
match made of wire/rod in diameter 2.5- mm.
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Figure
2
Design of Gamma- Match
for the RN3DEK 3- Element Directional Antenna for the 145- MHz
Band
Figure 3 shows Z of the antenna.
Figure
4 shows SWR of the antenna. Figure 5 shows DD of the antenna.
73! RN3DEK
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