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Re: [Antennaware] radials

To: "KC7VDA" <>,<>
Subject: Re: [Antennaware] radials
From: "David L. Foreman" <>
Date: Thu, 10 May 2007 14:49:02 -0700
List-post: <>
Good afternoon, Dan.

The Gap  Challenger Multiband DX antenna that the OPRC has or had available, 
uses three counter poise wires and from reading the manual,
and my emails with Gap, are buried just like radials, although you could 
elevate them with the antenna.
The person the answered my email to Gap asked my why I wanted to elevate the 
eitire antenna and counter poise system.
Below is what Gap says about the antenna.
CQ tested the Challenger and established that on 2m, for example, its gain was 
approximately 6 to 8dB. On 40m compared to a mono band vertical, they found 
Challenger an S unit stronger. This is typical of the many reports received 
from amateurs around the world. Challenger is designed to be mounted directly 
in the ground or elevated. A ground mount is provided with each antenna. With 
the ground mount in place, the Challenger simply drops in. If necessary, 
because of space limitations, but not to improve performance, Challenger may be 
roof mounted since it does not require earth loss to obtain a 50 ohm match. 
Challenger requires a counter poise of three 25ft. insulated wires. They may be 
buried or just scattered on the ground. Symmetrical deployment is not critical. 
Adding additional wire will not significantly improve performance. All of these 
are covered in a 16-page assembly manual provided with each antenna.

----- Original Message ----- 
From: "KC7VDA" <>
To: <>
Sent: Thursday, May 10, 2007 13:06
Subject: Re: [Antennaware] radials

> -----Original message-----
>> Today's Topics:
>>    1. Re: homemade coil (Andrew Ingraham) 
>> ----------------------------------------------------------------------
> Hello All;
> If you will pardon a newcomer ( to your group) for poking his " beazer"  into
> what appears to be an ongoing argument, an argument that I am sure will 
> continue
> as long as there are Hams and antennas, I have a few questions and a comment 
> or two.    
> First a question and a comment, an unkown writter makes the statement:
>> > with poor reports, running 600 watts.  I worked US hams at about 200
>> > miles with good reports.  However, I think that I can lay much of the
>> > blame for the reports on the fact that I have a single radial, slightly
>> > shorter than 1/4-wavelength.  Once I  establish a good mechanical
>> > connection and a reasonable  SWR, I will add radials (aiming for 60) and
> Does he really mean a radial or a counterpoise?
> if he really means a counterpoise, would the addition of  radials really do 
> any
> good? I am under the impression that radials were not needed where a counter-
> poise is used, that the counterpoise served the same perpose.
>> I have no personal experience with verticals (aside from engineering at AM
>> radio stations long ago), but from what I've read elsewhere, even a single
>> radial is OK *as long as it is not buried* or on/close to the ground.
> I too have served my time working with AM stations, the vertical of my station
> was surrounded by 160 radials that, after the first few feet, were burried 
> under
> egg sized rocks.  
> However,when working with Ham Band verticals, I have been under the
> impression that a minimum of 4 radial, each 1/4 wave length of the lowest
> frequency to be used was a necessity. ( and yes, I understand that more is 
> usually better, up to a certain point, ) Am I wrong about the length or does 
> it
> matter ? 
>> Elevated above ground, it's a counterpoise, you want it to be a quarter
>> wavelength long, and you need only one (though having only one might make
>> the antenna a little directional).  But once it's coupled to the ground, the
>> soil detunes it and ground losses go way up ... unless you've got a lot of
>> them.
> My experience here in Tucson, Arizona has been that burying radials up to 4
> inches below ground doesn't make any difference, I belive that the dry nature 
> of the local soil to be responsible for the low losses.
>> So to improve your signal, you could either run your single radial elevated
>> above ground, or bury 60 of them. 
>> The nice thing about buried radials, is that they can be shorter (about 0.1
>> wavelength) and they don't need to be tuned.
>> Regards,
>> Andy
> Yes, I fully agree, run as many radials as you can, make them as long as you 
> possibly
> can, keep them, preferably, above ground but bury them if you must, and you 
> will
> definitely improve your signal .
> To my way of thinking, the only thing that improves a good ( maybe a great ) 
> antenna 
> system is a good radial and ground system. 
> My only other comment would be that the radials don't have to be run in a 
> perfectly 
> straight line, the wires composing your radial system can be moved around as 
> needed 
> to clear obstructions ( read that as your better halfs Roses,  Mom's 
> Petunias, the side-
> walk or Juniors swing set, sandbox etcettra) . If that obsticle is a 
> beautiful yard full of
> grass that you are understandably reluctant to dig up, the solution is to 
> beg, borrow or
> otherwise scrounge a side walk trimmer. With it you can easily make very 
> nice, narrow,
> cuts in the grass, without any dirt being thrown up on the grass.  You then 
> simply stuff
> the radial wire into the cut you just made and when you next  water the grass 
> the cuts
> will  disappear.          
> O.K. thats my 2 bits worth, and should add a little more fuel to the fire, if 
> I have said 
> anything that you disagree with I am certain you will let me know and  I look 
> forward 
> to hearing it.
> 73 de kc7vda (Dan) 
>> ------------------------------
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>> End of Antennaware Digest, Vol 44, Issue 1
>> ******************************************
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