I'm sorry, I should have covered that. It is fed with RG-8. On 40 it
covers the entire band with SWR under 2 to 1. On 80 it is about 200 KHz
wide between 2 to 1 SWR points and on 160 about 75 KHz.
I hope that helps. Very 73.
Kevin, K7RX :)
-----Original Message-----
From: Blind-Hams For blind ham radio operators
[mailto:[log in to unmask]]On Behalf Of Steve Dresser
Sent: Saturday, February 15, 2003 18:23
To: [log in to unmask]
Subject: Re: Antenna Recommendation
Hi Kevin,
I have two questions. First, do you feed the antenna with coax or ladder
line? Second, do the traps cause the antenna to resonate in a very narrow
portion of the band?
Steve
On Saturday 2/15/03 13:02 Kevin Nathan wrote:
>Hi All,
>
>I just want to give a short review of my new antenna. It is the Alpha
Delta
>DX-A also known as the twin sloper. This antenna consists of two wire
>elements attached to a center mounting plate. One of these is
approximately
>67 feet long which works on 80 meters and the other is 55 feet long with a
>coil/trap arrangement in it called an iso-res inductor. This element works
>on 40 and 160 meters. The antenna attaches to one leg of a tower or can
>also be mounted to a nonconductive support. It uses the tower as the
ground
>return so if you use a nonconductive mount, it recommends the use of a down
>lead to a ground rod at the base of the support. The antenna looks just
>like an inverted vee when you set it up.
>
>Here it is mounted on a 50 foot Rohn 25G tower at about the 42 foot level.
>I have a Cushcraft A3 on the top of the tower along with a 3 element 6
meter
>beam and a vhf/uhf collinear. The directions and literature for the
antenna
>say it works best with such top loading. Alpha Delta may be able to give
>ideas for top loading when a beam isn't present.
>
>Now, for performance. Despite all the bad mouthing this antenna has taken
>over the years from antenna gurus, it is working like a bomb for me. So
far
>with only one real week of work I have worked V31FG on 160 the other
evening
>as well as a couple of long path QSO's to Europe which I mentioned on here
>before. Last night I got on in the contest on 40 meters and worked P40,
>KP4, PJ2, FM5 and others all with 100 watts from the Seattle area. Then, I
>went down on 80 and worked TG0, P40 and one other Caribbean station I can't
>remember without looking in the log. Admittedly, I did run about 600
watts.
>Then, this morning on 80 I worked several JA's, RU0 and BV.
>
>While it's not a power house antenna, it is certainly a better dx antenna
>than I've ever used on those bands. It also works very well on 30 and 17
>with the tuner in my rig. It does well with local contacts as well.
>
>All in all, for $60 U.S. this is a winner and a keeper. I just wanted to
>give people out there an idea for another antenna if they are looking and I
>appreciate you reading this.
>
>Thanks much and very 73.
>Kevin, K7RX :)
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