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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 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 vertically polarized with the antenna in 
    the vertical position or set-up parallel to the 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