There is a wullenweber antenna down in the San Diego area - south end of the
Coronado peninsula....not operational but the site is used by the Navy Seals.
Jim R. K9JWV
> Date: Mon, 4 Feb 2013 23:27:42 -0800
> From: charlesh3@msn.com
> To: topband@contesting.com
> Subject: Re: Topband: New 160M high performance receiving antenna at W3LPL
>
> Much much closer to home for us Pacific NW'ers:
>
> https://maps.google.com/maps?q=40+43+24+n,+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
>
> It looks to be operational and is still gated and guarded and has cars
> parked at the building.
>
>
> Chuck
>
>
> On 2/4/2013 10:53 AM, donovanf@starpower.net wrote:
> > Hi Lee,
> >
> > You can save yourself lots of engineering effort if you simply make
> > yourself a copy of this one:
> >
> > https://maps.google.com/maps?q=40+43+24+n,+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.
> >
> > 73
> > Frank
> > W3LPL
> >
> > ---- Original message ----
> >> Date: Mon, 4 Feb 2013 10:13:55 -0800
> >> From: "Lee K7TJR" <k7tjr@msn.com>
> >> Subject: New 160M high performance receiving antenna at W3LPL
> >> To: "Robert McGwier" <rwmcgwier@gmail.com>, "Frank Donovan"
> >> <donovanf@starpower.net>
> >> Cc: "Topband" <topband@contesting.com>
> >>
> >> 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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