Topband: New 160M high performance receiving antenna at W3LPL

donovanf at donovanf at
Wed Feb 6 12:09:53 EST 2013

Hi Peter,

Gablingen Kaserne looks abandoned, there's not a single car in the parking lot!   Not like in the "good old days" of the cold war in the 1970s and 1980s...


---- Original message ----
>Date: Tue, 5 Feb 2013 16:14:28 +0100
>From: "Peter Voelpel" <df3kv at>  
>Subject: Re: Topband: New 160M high performance receiving antenna at W3LPL  
>To: <topband at>
>There is still one in Germany as well:
>Peter, DJ7WW
>-----Original Message-----
>From: Topband [mailto:topband-bounces at] On Behalf Of Chuck
>Sent: Dienstag, 5. Februar 2013 08:28
>To: topband at
>Subject: Re: Topband: New 160M high performance receiving antenna at W3LPL
>Much much closer to home for us Pacific NW'ers:
>It looks to be operational and is still gated and guarded and has cars
>parked at the building.
>On 2/4/2013 10:53 AM, donovanf at wrote:
>> Hi Lee,
>> You can save yourself lots of engineering effort if you simply make
>yourself a copy of this one:
>> 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
>> 73
>> Frank
>> W3LPL
>> ---- Original message ----
>>> Date: Mon, 4 Feb 2013 10:13:55 -0800
>>> From: "Lee K7TJR" <k7tjr at>
>>> Subject: New 160M high performance receiving antenna at W3LPL
>>> To: "Robert McGwier" <rwmcgwier at>, "Frank Donovan"
><donovanf at>
>>> Cc: "Topband" <topband at>
>>>    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
>>>    received
>>>     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
>>>    affect
>>>     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,
>>>    W3LPL,
>>>     W5ZN, W1FV, NX4D, N4IS, AA7J, K1LT and many many others that
>>>    I
>>>     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.
>>>    Bob
>>>    >N4HY
>> _________________
>> Topband Reflector
>Topband Reflector
>Topband Reflector

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