[Antennas] Ground Mounted Vertical Radials

Fri Aug 22 00:11:55 EDT 2008

Benjamin "Ben" Wolfe, W3BC was a renowned expert on vertical antennas,
he wrote many engineering reports for the FCC and for Civil Defense on
broadcast towers and ground systems.

In the middle 1980s he always had a strong signal into the Mediterrean
Sea (Europe) where I was sailing as Radio Officer on a ship.  Night
after night, he would bomb in.  When I was down off of Brazil he would
bomb in.  He just was strong.

I finally asked him what he was running - as he loved to chat on CW -
and he said that he was using a quarter wave vertical on the peak of
his garage with the three elevated radials stretched into trees.  He
said that the garage was no more than 12 feet high and he made sure
that the radials were no lower than 10 feet as this was the minimum
height he had determined that they worked at.  He basically said that
you had to have the vertical and radials up ten feet on 40 meters but
that it worked better and was an easier install than a ground mounted
vertical with 120 wires.

So he said - he was an expert - but you don't know how much polish he
put the spin on the story - in other words bragging.  But he had an
exceptional signal - and was the first USA station to come through
every night.

That's good enough for me.  I'd guess that 20 feet woud be the magic
number for 80 meters.

Regarding an all band antenna of this type with no tuner.  You could
use stubs or you could use decoupling loops with capacitive tuning to
effectively form an insulator at that certain frequency as described
in Moxon's "HF Antennas for All Locations" by RSGB press available
through ARRL bookstore and elsewhere.

73

David N1EA

On Thu, Aug 21, 2008 at 11:35 PM, Billy Cox <aa4nu at ix.netcom.com> wrote:
> Good question Joe ... the "catch" here is trying to define
> and measure what "good operation" equals ... is that 3 dB
> worst, 6 dB worst or ? than a 120 radial ground mounted system.
>
> Do elevated systems work? YES. How well do they work? Depends.
>
> And plese keep in mind HF vs VHF/UHF are different settings.
>
> What works on 2m, as to the actual spacings above ground as
> measured in wavelengths ... is not going to be practical say
> on 160m or 80m for most amateur setups. There's the rub ...
>
> Though there is some new and interesting work being done by some
> in the broadcast industry using elevated systems ... many hams,
> after trying elevated radials systems end up going back to the
> 30-60 radial ground mounted systems.
>
> I be one of them! B-> While my elevated 80m 4x 'worked' and
> seemed to 'work well' ... comparisons with another local 4x,
> that used ground mounted radials ... mine was always behind.
>
> So my next rebuild of the 4x, will use ground mounted radials.
>
> Would I use elevated radials again? If it meant the difference
> between operating and not ... sure, but don't expect any 'free
> lunches' or miracles. RF engineering is more science than magic.
>
> Hope this helps!
>
> 73 de Billy AA4NU
>
> -----Original Message-----
>>From: Joe <nss at mwt.net>
>>Sent: Aug 21, 2008 11:23 PM
>>To: Chris Boone <cboone at earthlink.net>
>>Cc: 'Jerry' <n6vg at lanset.com>, antennas at mailman.qth.net
>>Subject: Re: [Antennas] Ground Mounted Vertical Radials
>>
>>I wonder how elevated an elevated system has to be for this to hold
>>true?  I would think it probably would have to be in terms of
>>wavelenghts?  Or at least that would make sence to me..  but could be wrong.
>>
>>Joe WB9SBD
>>
>>Chris Boone wrote:
>>
>>>If you ground mount, you are making a counterpoise...and what you are doing
>>>is coupling to the ground through the radials so insulated or non- doesn't
>>>matter much...however, if you raise the base 10-30ft OFF ground, you need
>>>only 4 radials for good operation..unlike ground mounted which requires MORE
>>>radials; the more wire in the ground, the better but elevated, you don't
>>>increase much past 4 radials...I have done a multiband vertical with 4 60ft
>>>radials and it worked great roof mounted. Check www.cebik.com for best info
>>>on antennas...IT IS the definite web site for antenna info. Its free to
>>>register...and the antenna info is at
>>>http://www.cebik.com/content/radio.html
>>>
>>>Chris
>>>WB5ITT
>>>
>>>-----Original Message-----
>>>From: antennas-bounces at mailman.qth.net
>>>[mailto:antennas-bounces at mailman.qth.net] On Behalf Of Jerry
>>>Sent: Thursday, August 21, 2008 8:20 AM
>>>To: antennas at mailman.qth.net
>>>Subject: [Antennas] Ground Mounted Vertical Radials
>>>
>>>Please reply off list to     n6vg at lanset.com
>>>
>>>Should buried radials for a ground mounted vertical
>>>be insulated or bare copper wire?  Or does it make
>>>any difference which one is used?
>>>
>>>Thanks.   Jerry N6VG
>>>
>>>
>>>
>>>______________________________________________________________
>>>Antennas mailing list
>>>Home: http://mailman.qth.net/mailman/listinfo/antennas
>>>Help: http://mailman.qth.net/mmfaq.html
>>>Post: mailto:Antennas at mailman.qth.net
>>>
>>>
>>>
>>>
>>>
>>______________________________________________________________
>>Antennas mailing list
>>Home: http://mailman.qth.net/mailman/listinfo/antennas
>>Help: http://mailman.qth.net/mmfaq.html
>>Post: mailto:Antennas at mailman.qth.net
>
> ______________________________________________________________
> Antennas mailing list
> Home: http://mailman.qth.net/mailman/listinfo/antennas
> Help: http://mailman.qth.net/mmfaq.html
> Post: mailto:Antennas at mailman.qth.net
>