Hi Csaba,
My experience is that an extensive radial system on the ground performs
significantly better than a few elevated radials. I suspect its difficult to
obtain nearly equal currents among a small number of elevated radials.
There is nothing wrong with gull wing elevated radials, but in my experience
they shorten the effective length of the vertical.
73
Frank
W3LPL
----- Original Message -----
From: "HA3LN" <csaba@ha3ln.hu>
To: donovanf@starpower.net
Sent: Wednesday, December 18, 2019 8:57:40 PM
Subject: Re: Topband: Temporary antenna suggestion for 160
Hi Frank,
So the gull-wing elevated setup should be dropped from the performance
point of view, right?
I have a 26m spider-pole and just wondering how to setup the radials for
that but considering you wrote no sense to make the radials into
gull-wing then.
Thanks and 73!
Csaba HA3LN / HG3N
http://ha3ln.hu/
On 2019-12-16 22:04, donovanf@starpower.net wrote:
> Hi Mike,
>
>
> Years ago my 4-square transmitting array used "gull-wing" elevated
> radials sloping 45 degrees from the feedpoint at ground level to about
> ten feet high.
>
>
> When I replaced the radials with sixty 120-foot radials laid on the ground
> I had to shorten the verticals by about five feet to maintain resonance,
> suggesting that the current at the bottom five feet -- or so -- of the
> verticals
> was attenuated by the sloping radials in close proximity to the verticals.
>
>
> As an aside, the performance of the array improved dramatically...
>
>
> 73
> Frank
> W3LPL
>
>
> ----- Original Message -----
>
> From: "Mike Waters" <mikewate@gmail.com>
> To: "thoyer" <thoyer1@verizon.net>
> Cc: "topband" <topband@contesting.com>
> Sent: Monday, December 16, 2019 8:52:41 PM
> Subject: Re: Topband: Temporary antenna suggestion for 160
>
> CORRECTION
>
> It was just pointed out to me that I neglected to mention that the
> feedpoint on my 160m inverted-L was much lower than 10 feet high!
>
> The tuner sits on the earth, and the two wires go straight up from that to
> the insulator block holding the antenna and the radials, which is less than
> 4 feet high.
> From that point, the two radials angle upwards at roughly 45° (?) to nearby
> trees, and level out at 10' high to the North and to the South all the way
> to the ends. (The South radial zigzags back and forth since the distance
> from the base to the neighbor's fence in that direction is less than 1/4
> wavelength.)
>
> I had photos of it online, but w0btu.com crashed. Looking for a place to
> upload it to.
>
> I hope this makes sense. Sorry for the lack of details below.
>
> 73, Mike
> W0BTU
>
>
> On Sun, Dec 15, 2019, 8:22 PM Mike Waters <mikewate@gmail.com> wrote:
>
>> Do the inverted-L, but use at least two 10' high 1/4 wave radials.
>>
>> Do NOT use an RF ground rod, or any radials on or near the earth. Just
>> connect the coax shield to the junction of the radials and any remote
>> tuner. At that point a good choke balun is necessary.
>>
>> Leaving out the choke or grounding the shield will result in very poor
>> performance.
>>
>> 73, Mike
>> W0BTU
>>
>>
>> On Sun, Dec 15, 2019, 7:04 PM thoyer via Topband <topband@contesting.com>
>> wrote:
>>
>>> With only 9 more to go for DXCC on 160 and all of the recent posts about
>>> how good the band has been recently "best in years....) I find myself with
>>> no
>>> antenna for the low bands and cringing after each post on how good the
>>> band has been.
>>> ...
>>> Options - I have a 45' tower with TH6DXX, 6m and 2m yagis. I could easily
>>> string a makeshift inverted L with about 45' vertical and around 100'
>>> horizontal. This I could string up in a few hours. the Horizontal portion
>>> would be pointed south. Not the best of configurations but that's what I
>>> have to work with. ...
>>>
>>> Tom
>>> W3TA
>>>
>>>
>>>
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