[Elecraft] Antennas for K1 Field Use

[Erik N Basilier]

Verticals can be very efficient with just one elevated radial.
Of course, such an antenna can be viewed as a dipole, so yes, dipoles are 
good!
Is it better to have one leg of the dipole horizontal at 8 ft or vertical?
My experience is that on dry and rocky ground horizontal is usually better, 
but only by a little, and not by anything close to 30 dB.
There are also big differences in performance depending on distance and skip 
angle etc, so the vertical can sometimes work better for an individual path.
Where the ground is wet with salt water I believe the vertical configuration 
will win by a good margin (I have no personal experience though), and many 
real-life situations may fall somewhere in between.
A good loading coil doesn't affect efficiency much as long as the antenna 
leg is shortened by less than 50%. On the upper bands it is rather easy to 
avoid loading coils altogether, either in homebrew configurations or using 
the extension rods offered by the commercial makers. However, if a 
horizontal dipole leg is shortened by a coil, it is still the same height. 
If a vertical is shortened, it will have less average height, giving it 
further disadvantage versus the horizontal, but again subject to great 
variations depending on the surroundings and propagation path. It doesn't 
hurt to have the capability to set up alternative configurations to find out 
what works best in a given situation.

73,
Erik K7TV

----- Original Message ----- 
From: "Mike Morrow" <kk5f at earthlink.net>
To: <elecraft at mailman.qth.net>
Cc: <kd8fip at gmail.com>
Sent: Sunday, July 12, 2009 7:19 PM
Subject: Re: [Elecraft] Antennas for K1 Field Use

> That would be very inaccurate.  HF vertical antennas for field use will 
> almost
> *never* have a proper and effective ground system.  Add to that the losses
> of loading coils/traps, and one will very certainly find *at least* a 30 
> dB difference,
> receiving and transmitting, in side-by-side comparisons between the 
> vertical and
> any simple wire resonant dipole.  That means six S-units.  That means a 
> one watt
> signal into the dipole will be better than 1000 watts into the vertical!
>
> The installation of a semi-effective ground system for the vertical would 
> require
> multiple tuned counterpoise wires that are far more troublesome to employ 
> than
> just using a simple resonant dipole.