[BC] Long Wire

[Glen Kippel]

On Tue, Feb 16, 2010 at 6:15 AM, Cowboy <curt at spam-o-matic.net> wrote:
 
> A true long wire is a l--o--n--g length ( several wavelengths ) of horizontally
> suspended, vertically polarized end-fire radiator, usually worked against
> an earth ground. A stake ( or several ) driven at or very near the
> end feed point. It's a bi-directional radiator. It can be worked against
> a radial ground system. Usually some number of short radials, mostly
> to simple increase surface area contact with the dirt. A terminated
> long wire will have a similar ground at the far end.
> A terminated long wire has a resistor at the far end to dissipate half
> the transmitter power, and is unidirectional toward the resistor.
> The gain of this array *can* be very high, and is proportional to the
> length of the wire. The more wavelengths, the tighter the beam.
> A true long wire has near zero broadside radiation, and a very low
> departure angle.
---------------
 
What you are describing here is a Beverage antenna, which is used for receiving.  These are fairly often used by MW DXers, especially in Finland.  I have a monograph published by the FCC, written by H. H. Beverage and describing the antennas used at the Grand Island and Podwer Springs monitoring stations.  Typical height abive ground for a proper Beverage is about 10 feet, though in Finland they usually just lay the wire across a frozen lake.
 
> The term long wire is sometimes used to refer to an end fed half wavelength
> wire, but that's a broadside array, more akin to a zep. If fed through a
> 1/4 wave feed line with the other side unterminated, then it is a zep.
> Any wire half wavelength or less is *never* correctly referred to as a
> long wire.

> Too many broadcast "engineers" refer to any length of wire, often vertical
> and much less than half wave as a "long wire" which is totally incorrect,
> and very misleading. That would correctly be referred to as a random wire,
> and like anything random, could be fed in any manor, against any ground,
> or none at all.

>--
>Cowboy