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Re: Topband: New 160M high performance receiving antenna at W3LPL

Subject: Re: Topband: New 160M high performance receiving antenna at W3LPL
From: Gary K9GS <>
Date: Tue, 05 Feb 2013 20:45:20 -0600
List-post: <">>
This topic made me curious to see what was on Google Maps:'57%22N+88%C2%B022'50%22W&ie=UTF8&ll=40.049563,-88.380675&spn=0.01636,0.038409&hnear=0x880ccc1bf72e2559:0x257eb5f56359d600,%2B40%C2%B0+2'+56.91%22,+-88%C2%B0+23'+15.98%22&gl=us&t=h&z=15

(may have to do some cut and pasting of the link.

Looks like not much left although the "circle" is still well defined for some reason.

On 2/5/2013 8:35 PM, Gary K9GS wrote:
Or there's this one in Champaign, IL at the University of Illinois.

It's been several decades since I've been out there and up close. In the
early 80s it was already in considerable dis-repair.

On 2/4/2013 12:53 PM, wrote:
Hi Lee,

You can save yourself lots of engineering effort if you simply make
yourself a copy of this one:,+141+19+44+e&hl=en&ll=40.72308,141.328892&spn=0.003313,0.006968&sll=40.723876,141.329155&sspn=0.026507,0.055747&t=k&z=18

My former employer (then Sylvania, now General Dynamics Advanced
Information Systems) installed it in 1966 at Misawa Air Base, Japan.
I believe its still exists, but its probably no longer in use due to
technical obsolesence, high maintenance costs and unavailability of
spare parts.  An identical array installed at Elmendorf Air Base,
Alaska is also still in existence as far as I know.  Maybe you can
purchase one of them!

Many copies of the original 40 element German "Wullenwever" array were
built all over USSR shortly after World War II, some may still exist.
Among other things, they tracked the 10 and 20 MHz Sputnik beacons
that some of us recall.


---- Original message ----
Date: Mon, 4 Feb 2013 10:13:55 -0800
From: "Lee K7TJR" <>
Subject: New 160M high performance receiving antenna at W3LPL
To: "Robert McGwier" <>, "Frank Donovan"
Cc: "Topband" <>

   Hello Bob and all, Yes I agree on the issue of needing the
   stable impedance
    from the elements to drive the passive systems. I still have
   some questions
    in my mind about the radials and here is why. I have made
   many field tests
    where I measured the actual phase and amplitude differences
   between two
    receiving elements where one is held constant and parameters
   around the
    other were changed such as ground rods, radials, and such.
   Both were
    receiving signal from an equidistant transmitted source.
    What I can tell you
    for sure about this is that with a Hi-Z system the phase and
   amplitude shifts
    become quite unstable when radials are used. I do not know
   this to be a
    fact with loaded elements but I have seen evidence of  some
    signal shift due to the presence of the radials to the
   element. This test really
    opened my eyes about received signals and what objects might
    them. I have plans to buy the NEC4 engine and do some more
   field tests
    using another technology that should give me more answers. It
   is these
    minute details that prevent us from making these RX antennas
   even smaller.
     There is no doubt that the state of the art is advancing in
   receiving antenas
    with all the work that is and has gone on. I am confident
   that what we are
    presently doing is not perfect and I expect the state of the
   art still has a ways
    to go. There have been many man years of work by many people.
   I hesitate
    to name calls but a few notables are K6SE, W7IUV, W8JI, K9AY,
    W5ZN, W1FV, NX4D, N4IS, AA7J, K1LT and many many others that
    apologize for not having the space here or personal memory at
   the moment
    to mention. There are more man years of work to do.
       I still covet the 96 element Wullenwever antenna invented
   around 1940!
   Lee  K7TJR

   >The issue is getting sufficient ground radials so that
   changing soil conditions: dry season, wet season, etc have
   minimal impact on the impedance which is the easiest
   measurement of the changing conditions.  Joel and I did
   measurements several times and when he was near drought he
   found he had to add radials to stabilize the performance.
    Once done, his system has been stable since.
   Great news on both of you successfully deploying.

Topband Reflector



Gary K9GS

Greater Milwaukee DX Association:
Society of Midwest Contesters:
CW Ops #1032

Topband Reflector

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