On Feb 6, 2:52*pm, Kevin Alfred Strom
wrote:
On 2/6/2011 1:25 PM, dave wrote:
[...]











- It's the new one. Well, yes, that's right, an inverted L. The
- vertical is about 30 feet, the horizontal about 60. Oriented
nearly
- north-south (not checked with a compass), far end is south.
Guatemala
- is off the forward left side if you looking the direction the
antenna
- is aimed.

BpnJ,

'The Antenna's Size' is "The Antenna's Size" : A Fixed Point
-how-ever- as the Frequency Varies for 500 kHs to 1 MHz
to 2 MHz to 4 MHz to 8 MHz to 16 MHz to 32 MHz
the Propagation Characteristics of the Antenna ~change~
So having the Vertical-Up-Leg as your Starting Reference
Point and your Far-End as your End-Point should/would
allow you to have an Idea {Hunch} about the Receiving
Properties of your Fixed Size Antenna on any given
High {Shortwave} Frequency [HF].
.
.
- How much does the 30 vertical do for you, other than
- collect vertically polarized QRM?

How better to get to your 60 Foot Out-Horizontal-Arm
1/3rd Omni-Direction Vertical Antenna
+plus+
2/3rds Off-the-Sides Horizontal Antenna*
-and- 45 Degree Out-from-the-Sides Horizontal Antenna*
-and- Off-the-End Horizontal Antenna*
* Depending on the Frequency
.
- The only reason, really, I built it this way was to
- allow the 9:1 antenna unun to be mounted near
- ground (the ground is not in place yet, but will be
- soon). Otherwise, I would have put the whole thing
- up high, or possibly sloped with the unun end down.

Close to the Ground is 'good'.
.
- This morning (1800z onward), the VOA relays from
- MDG and BOT (Africa) on 16 and 19 meters were
- coming in almost like locals.
-
- Bruce

Strong Signals and less noise is good too ) ~ RHF
.
.

Actually, isn't the directionality of a wire along it's axis? That's
how the PAR end-fed SWL antenna is, according to Dale...

That is a very complicated subject. Usually a wire close to the
ground has a pattern between a kaleidoscope and a butterfly on acid.
Seriously, like a butterfly more often than not, with various lobes
and nulls depending on the frequency.

Bruce:

I have EZNEC, which is a very good antenna modeling program. I
modeled your antenna for various frequencies and created a fairly
readable 3D plot of its pattern on various frequencies. In each
case, the horizontal wire points in the opposite direction from the
Y axis shown in the plots:

1 MHz:http://liberty.3950.net/Jensen%201.PNG

5 MHz:http://liberty.3950.net/Jensen%205.PNG

6 MHz:http://liberty.3950.net/Jensen%206.PNG

7 MHz:http://liberty.3950.net/Jensen%207.PNG

10 MHz:http://liberty.3950.net/Jensen%2010.PNG

15 MHz:http://liberty.3950.net/Jensen%2015.PNG

17 MHz:http://liberty.3950.net/Jensen%2017.PNG

22 MHz:http://liberty.3950.net/Jensen%2022.PNG

With all good wishes,

Kevin, WB4AIO.
--http://nationalvanguard.org/http://kevinalfredstrom.com/

Wow! These are amazing! Thanks, Kevin. I am somewhat surprised,
though, by the apparently omnidirectional character (at least
horizontally) on the lower freqs. The higher end looks like a
mathematical nightmare!

One thing notable too, is the lower angle of radiation on the higher
freqs. I wish I could attain those on the lower ones - but the only
way to do that is go higher, I guess.