That's a good question - especially since it relates to your arid soil
- vs my "average" Midwest soil here in Ohio.
Ive done no pattern calculations.
But based on 15 years of reading and personal observations with my 1/4
wave INV-L ( that has grown ( vertically through a black walnut tree)
from 15 ft tall to 52 ft tall, and from one ground rod and zero
radials to the same ground rod and 26 radials, here is what I can say:
1. Have heard of a fat lobe with up to 3 dB gain in the direction
opposite the horizontal/sloping wire. ( For me, that direction is W
towards 6/7-land. I do very well that way, out into the Pacific ( KH6
and VK/ZL.)
2. I did surprisingly well with no radials and just a 15 ft vertical
leg, running 100w. Wkd LZ/4X4/JA my first winter from this qth when I
didnt think it was possible.
3. Adding a kw amp (10 db) made the biggest improvement in dxing,
compared to anything I did with the L.
4. The L seems to be omnidirectional as you would expect.
5. As I began to add radials, the swr went down for the first 10-12
radials, then slowly increased until I reached 26 radials, after-which
it plateaued. So I stopped adding radials.
6. Although arid soil isnt supposed to work well with verticals, there
are some big sigs from guys in AZ so I assume many/more radials make
up for the poor conductivity soil. Probably a lot more than I need.
7. My current INV-L has been good for >1000 Q's when I put in the time
in 160 contests, and 164 confirmed DX entities to date.
8. My yard is former farm land, sloping less than 10 degrees.
9 In contests I have no trouble working N-S-E-W. It varies quite a bit
from contest to contest.
10. I use a SAL-30 rx antenna. No Beverages or short vertical arrays.
Id be interested in hearing how the addition of radials affects your
swr. What your radial lengths are. Wire type? And what you are
working/directionality?
The lengths of my 26 radials vary due to my sole walnut tree not being
in the center of a 200x700 ft lot. Its off to one side so my radials
vary from 30-130' in length, consisting of #12 & 14 (Cu) and #17 (Al)
wire. Most are bare Al cheap fence wire. All are on the grass. I need
to roll them up for lawn mowing season. If I dont, then I eventually
do, around the tractor blades.
Bob
-----------------------------------------From:
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To: topband@contesting.com
Cc:
Sent: Monday January 15 2024 12:00:56PM
Subject: Topband Digest, Vol 253, Issue 18
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Today's Topics:
1. Inv L Radiation Patterns? (Steve Harrison)
2. Re: Inv L Radiation Patterns? (Charles Morrison)
3. Re: Inv L Radiation Patterns? (Rob Atkinson)
----------------------------------------------------------------------
Message: 1
Date: Sun, 14 Jan 2024 17:59:22 -0800
From: Steve Harrison
To: topband@contesting.com
Subject: Topband: Inv L Radiation Patterns?
Message-ID:
Content-Type: text/plain; charset=UTF-8; format=flowed
Has anybody plotted the radiation patterns for inverted Ls on 160?
I'm
particularly interested in those for relatively-low antennas, say 40
ft
max, over fairly-poor ground such as desert sand with the water table
perhaps 120 feet down.
TNX,
Steve K0XP
On 1/2/2024 6:56 AM, VE6WZ_Steve wrote:
> Today I uploaded a short 6 minute video showing how to use the Kiwi
radios located all over the world to test your transmit antenna.
>
> How is the front-to-back on your 4 square really performing?
> It the dipole or the vertical performing better on the DX path?
> Make an azimuth polar plot of your Yagi and see how it compares to
modelling. How does the pattern change across the band?
>
> This is not a new thing, but in this video I describe the method
for those that may not be familiar with it.
> No test equipment is needed. All that?s required is a PC sitting
beside your radio.
>
> Using the ?S-meter? function on the Kiwi radios makes it quick and
easy to record signal levels from your transmit antenna.
> This method is far more accurate than trying to estimate a signal
level while watching a bouncing analog or digital S-meter.
>
> https://youtu.be/_BMeVJQ_cwI [1]
/> >
> 73, es HNY to all
> Steve, VE6WZ
> _________________
> Searchable Archives:http://www.contesting.com/_topband [2] -
Topband Reflector
--
NO on ARRL Bylaw 46!!! See my QRZ.com page at
*https://www.qrz.com/db/K0XP*
/>
------------------------------
Message: 2
Date: Sun, 14 Jan 2024 21:59:30 -0500
From: Charles Morrison
To: topband@contesting.com
Subject: Re: Topband: Inv L Radiation Patterns?
Message-ID:
Content-Type: text/plain; charset="UTF-8"
The modeling i?ve seen plus my own has been +~ 1 to 2dB for 50 - 70
ft
vertical sections
-Charlie N1RR
401-742-7240 8AM - 9PM
*E-mail*: n1rr@n1rr.com
*Website*: www.n1rr.com
*Youtube channel*: NovemberOne RomeoRomeo
https://www.youtube.com/channel/UCPDzEf57Ad80cVKOiLZLB7w/videos
/>
On Sun, Jan 14, 2024 at 8:59?PM Steve Harrison wrote:
> Has anybody plotted the radiation patterns for inverted Ls on 160?
I'm
> particularly interested in those for relatively-low antennas, say
40 ft
> max, over fairly-poor ground such as desert sand with the water
table
> perhaps 120 feet down.
>
> TNX,
>
> Steve K0XP
>
>
> On 1/2/2024 6:56 AM, VE6WZ_Steve wrote:
> > Today I uploaded a short 6 minute video showing how to use the
Kiwi
> radios located all over the world to test your transmit antenna.
> >
> > How is the front-to-back on your 4 square really performing?
> > It the dipole or the vertical performing better on the DX path?
> > Make an azimuth polar plot of your Yagi and see how it compares
to
> modelling. How does the pattern change across the band?
> >
> > This is not a new thing, but in this video I describe the method
for
> those that may not be familiar with it.
> > No test equipment is needed. All that?s required is a PC sitting
beside
> your radio.
> >
> > Using the ?S-meter? function on the Kiwi radios makes it quick
and easy
> to record signal levels from your transmit antenna.
> > This method is far more accurate than trying to estimate a signal
level
> while watching a bouncing analog or digital S-meter.
> >
> > https://youtu.be/_BMeVJQ_cwI [3]
/> > >
> > 73, es HNY to all
> > Steve, VE6WZ
> > _________________
> > Searchable Archives:http://www.contesting.com/_topband [4] -
Topband
> Reflector
> --
> NO on ARRL Bylaw 46!!! See my QRZ.com page at *
> https://www.qrz.com/db/K0XP*
/> > _________________
> Searchable Archives: http://www.contesting.com/_topband [5] -
Topband
> Reflector
>
------------------------------
Message: 3
Date: Mon, 15 Jan 2024 05:32:33 -0600
From: Rob Atkinson
To: topband@contesting.com
Subject: Re: Topband: Inv L Radiation Patterns?
Message-ID:
Content-Type: text/plain; charset="UTF-8"
A bit more field intensity extends in the direction opposite the
direction of the horizontal part of the inverted L element.
73
Rob
K5UJ
------------------------------
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