On 12/11/2020 3:55 AM, Rob Atkinson wrote:
The only thing about this I advise in the way of a change is something
W1BB recommended,
Again, I refer to N6LF's monumental work.
73, Jim K9YC
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On 12/11/2020 2:02 AM, Artek Manuals wrote:
However I have always wondered about elevated radials . The NEC ( both 2
and 4) models (not that those are to always be trusted) show very little
(if any) improvement beyond four elevated radials, you have any theories
on why that is? Intuitively (als
Rudy Severns has many plots of elevated radial numbers, lengths, and
elevations on his web site antennasbyn6lf.com
My "T" showed the expected change in feedpoint Z as I added 125ft long
10ft elevated radials from 2 to the current 8. The last two made no
measurable difference. From Rudy's an
Over really good dirt there isn’t too much difference.
The other problem is that the NEC ground approximation coding usually
underestimates loss. This is because the ground approximation in the model
uses a monolithic ground. Same stuff 100 feet down as at the surface. Real
dirt never is. Water ta
> IMHO, for that number, on-the-ground radials do not need to be anywhere near
> that long. Personally, I subscribe to the same-length-as-the-vertical
> guideline.
The only thing about this I advise in the way of a change is something
W1BB recommended, which was that the radials on the ground g
Jim et all
I agree with what you say on all points when it comes to radials on the
ground and salt water affects.
However I have always wondered about elevated radials . The NEC ( both 2
and 4) models (not that those are to always be trusted) show very little
(if any) improvement beyond four
On 12/10/2020 11:14 PM, Raymond Benny wrote:
With said, I believe my ground absorption is very high so I feel the higher
numbers of radials helps greatly with my vertical efficiency and radiation.
Hi Ray,
The soil affects us in two important ways. First, poor soil burns
transmitter power unde
Yes, Mark, N5OT go back a long way, 80's or so.
At my QTH, Arizona high desert 4800ft, the soil is very non-conductive -
typically dry shale and small rocks, it's called Caleche. We have very
little rain, about 10" - 12" per year. Humidity very seldom goes above 30%,
and temps in the summer are in
N6LF Rudy's web site and associated QEX series has empirical data to
answer all of these questions regarding the number and length of on
ground radials.
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 12/10/20 11:14 AM, Mark - N5OT wrote:
Yeah. I don't claim to be a radial expert but
Especially if you have elevated radials you will need a choke otherwise
the coax and your shack will become part of the ground plane. . In my
case I have a choke ( for common mode currents) and UNUN to match the 25
ohm impedance of the antenna to 50 ohms. In some installations the
common modes�
On 12/10/2020 4:33 AM, Rob Atkinson wrote:
I've never understood what is gained by using a balun at the feedpoint
in this application. The feedline is unbalanced as is the load.
What's the point of a balun.
That's the problem with the word "balun." A CHOKE is needed at the
feedpoint so that
Yeah. I don't claim to be a radial expert but I do claim to have a lot
of experience working other stations on 160 meters.
My buddy W9RE told me on a DXpedition once that he built a dipole laying
on the ground and it resonated on 160 when the wires were about 80 feet
long.
Ray, with respect
>
> To model radials, we must use Real High Accuracy Ground, with NO connection
> to Ground. Read the EZNEC manual
Yes! That is what I need to change. Thank you!
Solution:
I was connecting the radials to ground using EZNEC. I need to create the
radials just above ground.
Page 90 of the User
IMHO, for that number, on-the-ground radials do not need to be anywhere near
that long. Personally, I subscribe to the same-length-as-the-vertical guideline.
My inverted-L is 55 feet of vertical tubing plus the horizontal wire. My
insulated, on the ground radials are 55.5 feet (9 radials out
I've never understood what is gained by using a balun at the feedpoint
in this application. The feedline is unbalanced as is the load.
What's the point of a balun. The wild variations in R and X over the
range of the band will likely result in heat and loss at the balun.
If the point is to keep
On 12/9/2020 8:51 PM, wi6x...@gmail.com wrote:
The radials as modeled have End1 Ground connection and no End 2 connection.
Should they be connected to another wire?
To model radials, we must use Real High Accuracy Ground, with NO
connection to Ground. Read the EZNEC manual carefully about tha
Thank you everyone.
The radials as modeled have End1 Ground connection and no End 2 connection.
Should they be connected to another wire?
--- WIRES ---
No. End 1 Coord. (ft) End 2 Coord. (ft) Dia
(in) SegsInsulation
If your vertical is ground mounted you need alot more. I'd say atleast 36
radials, 135ft long. It will make a big difference in your signal and be
easier to match.
I have over 100 radials but probably an over kill, but I feel I have a good
signal on 160m.
Ray,
N6VR/ W7YA
On Wed, Dec 9, 2020, 3:5
Jim,
It looks like you connect wires to lossy ground. Do you have the NEC-4
engine with your EZNEC ver 6.0?
Carl K9LA
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60 + j19 does seem off. Is this ground mounted or with elevated radials?
An EZNEC free-space model reports *36 +j227* at 1800kHz.
On perfect GND it reports 166 +j306 ohms.
10' above 0.005/13 GND it reports *37 +j262* ohms with resonance at 1510kHz.
Dave KH6AQ
On Wed, Dec 9, 2020 at 11:32 AM J
On 12/9/2020 12:00 PM, wi6x...@gmail.com wrote:
My gut tells me the 60.25197 + J 18.63926 ohms impedance is to high, but I
don’t have enough experience to know if what what I am doing is correct or not.
I’m a neubie, at EZNEC and 160m.
Those numbers tell you that the antenna is resonant below
I need help proofing an Inverted L model I made please. 40’ x 143’, four 100’
radials, #14 wire.
My gut tells me the 60.25197 + J 18.63926 ohms impedance is to high, but I
don’t have enough experience to know if what what I am doing is correct or not.
I’m a neubie, at EZNEC and 160m.
Thank you i
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