I tested lots antennas
on the Air. The simplest and most efficiencies ones are vertical
delta antennas. Below there are figures of the antennas that were
tested by me. Antennas for 40- 10 meter band were installed
on the 8- meter mast. First 4 meters it was a metal tube then another
four meters were bamboo poles. Each antenna was placed on a separately
mast. Antennas were fed through 50 Ohm coaxial cable (each antenna
through own cable). It does not matter where the central core of
the coaxial cable is connected- to lower or higher side of the antenna. |
The antennas are self-symmetrical
antennas (it was proved by UR0GT) so it is not needed balun
1:1 or RF choke (ferrite rings on the coaxial cable) at the feeding
terminals. Antennas made exactly on the sizes on the figures should
be have resonance inside of the band, however in certain circumstances
it may be need some adjusting of the antenna length.
73! de RZ9CJ
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