Original article from: Wayne Sarosi
Reposted by Rob Dennis,Moderator HAM_TECH,for use of the FIDO HAM_TECH echo.
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SUBJECT: Wire antennas- part 3
In this posting I will be discussing some of the different wire antennas
the we use in the amateur world.
These antennas are:
o Long Wire, closing remarks.
The long wire antenna was discussed in the previous posting.
I would recommend this antenna for those interested in a continued contact
postion with a specific station. Long enough,the longwire can provide very
good signal in the direction of the antenna for fixed communication.
o Wire Dipole
Simple to make and inexpensive to buy.
It's the basic design for Inverted Vee. Basically a bidirectional antenna
with a balun. Antenna is null of the tips.
The dipole is 2.12 dB over isotropic and is and electrical halfwave.
Can be arranged vertically or horizontal. It is a linear antenna.
o Inverted Vee
This antenna is a dipole with sloping elements.
The antenna is omni-directional for the most part.
It's overall gain is less than a dipole because of the omni pattern.
o Rhombic
This is a rather large antenna. Rhombics can be various lengths total.
In the UHF range,19 wavelengths is common.
In HF,4 and up is common. This antenna requires some land depending on the
frequency.
A rhombic is good to twice it's design frequency, directional,and fixed.
o Terminated longwire
Requires some space,but performs well. Directional with a wider bandwidth
than the longwire at shorter lengths.
o Sloping Vee
Similar to the Inverted Vee,the sloping vee is semi-directional.
Easy to install,inexpensive,and easy to build.
o Beverage
Good all band antenna with a tuner. Easy to build and set-up.
Requires some space and not suitable for small lots.
o Marconi
Large antenna requiring some space,but good for the lower HF bands.
Semi-directional,the marconi is easy to build and cheap to construct.
o Folded Marconi
Cheap and easy to install antenna. Made from 300 Ohm ribbon cable (TV).
Set up in a `hockey stick' form. Use a tuner.
Works well in the 40-160 range. Requires a ground plane.
o Loop
Consists of a full wave length and can be set-up horizontally or
ertically
polarized with the antenna in the vertical position or set-up parallel to
he
ground for lower frequencies.
o Sloper
Common design for most hams.
Antenna is a slooping dipole or sloping quarter wave.
Easy to bulid and install.
Semi-directional in the direction of the slope.
-WS
--- GoldED 2.42.G1219
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* Origin: VE3SJN....Moderator....HAM_TECH (1:163/506.4)
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