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Re: [TenTec] New and Improved Terminology (NVIS origins)

To: tentec@contesting.com
Subject: Re: [TenTec] New and Improved Terminology (NVIS origins)
From: Rsoifer@aol.com
Reply-to: Discussion of Ten-Tec Equipment <tentec@contesting.com>
Date: Fri, 7 Jan 2011 09:20:19 -0500 (EST)
List-post: <tentec@contesting.com">mailto:tentec@contesting.com>
My experiences lead me to go even farther.  I have an elevated (10  feet 
above ground) Hy--Gain AV-640, which is a 3/8-wave multi-band vertical  with 
top hats and four 6-foot counterpoise rods.  My QTH is about two  miles from 
our club station, which has a 3-el SteppIR on a 40-foot tower.   I really 
needed BS7H (it was the last country on my need list) so for a time  during 
the 2007 expedition I went back and forth between the two stations.   The 
vertical consistently beat the low beam, by at least an S-unit.  In  contrast, 
in the weekly club net on 20 SSB, which is all domestic, the beam wins  by a 
comparable margin.  If the beam were higher, I have no doubt that it  would 
beat the vertical on long-haul paths, but at its present height, the  
vertical's low angle wins.
73 Ray W2RS
In a message dated 1/7/2011 2:03:49 P.M. GMT Standard Time, n4ydu@yahoo.com 
I've not  had a lot of success with vertical dipoles and limited success 
with 1/4  verticals on 40M. However, they both have their place. I think it is 
important  to remember what the desired results for a particular situation. 
A low dipole  on 40M (say 30 to 50 feet) is an excellent high angle 
radiator and is very  difficult to beat fo domestic contesting and ragchewing. 
have both a  quarterwave vertical (8 1/4 radials about 8 feet off the ground) 
and a low  dipole for 40M (as well as a high dipole) and the low dipole 
always wins over  the vertical for domestic stuff and is often hard to beat for 
DX in the same  direction. However, the vertical sometimes wins for long 
haul DX such as  JA and UAO.

In all cases, my high dipole at 75 feet oriented to  Europe is always 
significantly (6 DB or more) stronger than the vertical to  Europe.

That given, I agree with Rick that if you are limited to  vertical space, a 
1/4 vertical with four elevated radials is a practical  way to go - 
especially for DX. But if you can get a dipole up to 50 feet  of height, you 
probably in better shape than the  vertical.



--- On Thu, 1/6/11,  Rick - NJ0IP / DJ0IP <Rick@DJ0IP.de> wrote:

From: Rick -  NJ0IP / DJ0IP <Rick@DJ0IP.de>
Subject: Re: [TenTec] New and Improved  Terminology (NVIS origins)
To: "'Discussion of Ten-Tec Equipment'"  <tentec@contesting.com>
Date: Thursday, January 6, 2011, 4:16  PM

James, that is a tough call because it is not really apples to  apples.

A specific answer to your question, as compared to "my"  vertical dipole,
then I must say I believe the raised quarter wave vertical  with 4 elevated
radials, say about 10' off the ground will be the better  antenna; but the
difference will be very little.  I don't believe it  would be more than 3dB,
and if anything, less difference.

If we were  to take a full size vertical dipole, it would be 66' high, plus
allowing  for a couple of ft. raised off the ground, you need nearly 70 ft.
This is  very impractical.  But then as I understand it, it would be  
better than the raised quarter wave with 4 elevated  radials.

So my ranking:

1. Vertical dipole, full size, raised  4', total 70' height
2. Quarter wave vertical, raised 10', total 43'  height
3. Vertical dipole (2x 20') raised 4' off the ground, total  44'


#1 is expensive to implement and darn high.  A  60' Spiderbeam fiberglass
pole costs $300 and would have to be  extended.

#2 also needs 66' total of horizontal space (33' in 4  directions) at a
height of 10'.  You will have to come up with 4  elevated tie points (trees,
house, mast, something).

#3 needs only a  40' pole (Spiderbeam: $120), plus 2x army surplus 
poles ($10)  and a T-Post (fence post, $5). The mast is $135 altogether.

And the  performance difference of the three, in my humble and totally
unqualified  opinion, would be about like the difference between a K3, an
Orion 2, and  an Eagle.

ONCE AGAIN I have to stress that I usually operated portable  and options 1
and 2 would almost never have been feasible.

For my  portable VD, I used the feedline as a guy wire in one direction, and
then  2x 30' pieces of thin Dacron of Kevlar rope countering it.  That  
the antenna straight and stable (assuming a good quality heavy  duty
telescoping pole, such as the Spiderbeam poles).

Bottom  Line:
- For home use, I would favor option 2 (4 raised radials) if I had  the
- For portable use or installations with tight floor space, I  would favor
option 3 (shortened VD)


-----Original  Message-----
From: tentec-bounces@contesting.com  [mailto:tentec-bounces@contesting.com]
On Behalf Of Richards
Sent:  Wednesday, January 05, 2011 9:37 PM
To: Discussion of Ten-Tec  Equipment
Subject: Re: [TenTec] New and Improved Terminology (NVIS  origins)

Do you claim your vertical dipole works better than a quarter  wave with 
four good, properly tuned/cut elevated radials?

Reason I  ask is that my aluminum rotatable dipole project has technical  
problems  (The alum elements sag and dip and wave in the wind too  much 
-- I did not select sufficiently large diameter and stiff tubing....  but 
ham radio is for experimenting, right...?)   AND I  was
thinking I could salvage the project by turning the floppy thing  
vertical and make it a vertical dipole - OR - I might convert it into a  
single tubing vertical elevated ground plane and add some wire  radials.

Any traction ?     (I will stick my neck  out here... re: your 
challenge... and expect the properly tuned elevated  radials to equal the 
work of the second half of the vertical dipole and  say they should 
perform equally well.   N'est ce  pas?)

================== James - K8JHR   ====================

On 1/5/2011 8:42 PM, Rick - NJ0IP / DJ0IP  wrote:

> I have used the vertical dipole instead of the classical  vertical because
> my despise for radials.

> I  still stand by my challenge for anyone to come up with a simple cheap
>  antenna that will out-perform the simple vertical  dipole.

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