Let me throw in a few comments and a question or two. I have the Alpha
Delta DX-A. It is essentially a sloper with both sides active antennas.
One side is for 80 meters and the other side is for 40 and 160 - which
has 1/4 wave for 40 meters and then a loading coil to make up for 160.
(Each side is connected to the center conductor of the coax. The shield
is grounded to the tower and I have a separate ground wire going down to
a ground rod).
Well, I have worked about 56 DXCC (including all continents) on 160 but
can't seem to hear anything active lately that I don't have in the log.
The antenna seems very poor on 80 meters but that has not been a focus.
I did work WAS on 160 mtrs with this antenna and it seems to do ok with
close in contacts (I live in Texas and the 50 states were somewhat close
in - with Alaska and Hawaii being a bit harder).
The question is that I am wondering if I could modify this antenna to
make it more optimized for 160 meters - and if it sacrifices 40 and 80
that is fine as I now use a 3 ele on 40 and 80 is not a concern that I
have DXCC on that band. My initial goal is DXCC on 10-160 and have done
that except for 160. So, any ideas about optimizing this AlphaDelta
antenna for 160 would be appreciated.
Gary, N5PHT
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of Bill Axelrod
Sent: Monday, June 19, 2006 12:18 PM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] 160M Inverted Vee
I just can't resist sending this post.
One more take it or leave it observation about an 160M inverted Vee.
Mine
is hung off of my tower with the apex at 70ft and the ends at ~20 ft.
And sure, it is a better receiving antenna than my vertical - IF and
only
IF - I measure "better receiving antenna" by the noise level.
Certainly,
it's a whole lot quieter than the vertical. It doesn't hear all the
noise.
Unfortunaly, it also doesn't hear signals all that well unless they are
close (100 to 1000 miles). Seems to me that's the real issue.
It doesn't transmit all that well. Does a great job on USA QSOs out to
the
midwest. But there's lots of DX I can't hear. And more that can't hear
me
on the Vee.
Despite that, I worked about 50 countries on 160 this past winter
season,
and a small number of "real good" DX at that. So what?
Am I happy with it? Heck no. New vertical and beverages going up this
week.
So, all the emails bragging about working so many countries or some rare
DX
don't testify to how good any electrically low 160M inverted Vee is.
Nor
does it matter how "quieter" it is. That's not the issue. What matters
is
how does it compare to that vertical for transmitting, or that beverage,
K9AY loop, etc for receiving. The laws of physics will dictate the
results.
I'd be leery of those who claim an exemption.
73... Bill K3WA
----- Original Message -----
From: "K4SAV" <RadioIR@charter.net>
To: <towertalk@contesting.com>
Sent: Monday, June 19, 2006 12:19 PM
Subject: Re: [TowerTalk] 160M Inverted Vee
>I have seen two posts now claiming that an inverted vee works better
> than a vertical for receiving on 160 meters for both DX and local (at
> least for the persons posting). I'm not disputing these claims, but I
> don't understand them.
>
> I am assuming when someone says "quiter", they mean a higher signal to
> noise ratio.
>
> It seems to me that a properly constructed short inverted vee will
have
> a big lobe straight up on 160, and overall, a higher response angle.
So
> what is it about an inverted vee that makes it better for your
> situation? Any speculation?
>
> If you say the signals are actually coming in at a high angle, that
> would say that the inverted vee would also work better than a
beverage.
>
> Here's a piece of information that may/or may not be helpful. An
> inverted vee that is very short (very high SWR), fed with coax and no
> balun, will have high common mode feedline currents, and function a
lot
> like a vertical. If the feedline is placed next to something, like a
> tower, the feedline will couple to the tower.
>
> Jerry, K4SAV
>
> Richard (Rick) Karlquist wrote:
>
>>>Seriously though, such statements are of no value unless you include
>>>a lot more information. If you expect me to believe the 20 dB figure
>>>for all signals from all directions at all times of day...
>>>
>>>
>>
>>We listened all night long during a 160m contest to stations in
>>all directions, near and far. The vee never compared to the vertical.
>>It may be, that once in a while, the vee would have been useful,
>>although I never observed that; but this test convinced me that
>>if I had to pick one of the other (for transmit), I would take
>>the vertical any day.
>>
>>The vee (any vee, even a 40 meter vee) is better on receive
>>than any vertical, at my QTH.
>>
>>Rick N6RK
>>_______________________________________________
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>
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>
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>
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