On 1/6/2011 3:16 PM, Rick - NJ0IP / DJ0IP wrote:
> 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.
Probably in the real world about 2.8 dB.
73, Jerry, K0CQ
>
> 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 slightly
> 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'
>
> BUT...
>
> #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 fiberglass
> 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 keeps
> 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
> room.
> - For portable use or installations with tight floor space, I would favor
> option 3 (shortened VD)
>
> 73
> Rick
>
> -----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
> of
>> 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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