Topband: New 160M high performance receiving antenna at W3LPL
donovanf at starpower.net
donovanf at starpower.net
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...
http://www.amerika-in-augsburg.de/index.php?id=1363
73
Frank
W3LPL
---- Original message ----
>Date: Tue, 5 Feb 2013 16:14:28 +0100
>From: "Peter Voelpel" <df3kv at t-online.de>
>Subject: Re: Topband: New 160M high performance receiving antenna at W3LPL
>To: <topband at contesting.com>
>
>There is still one in Germany as well:
>
> http://maps.google.com/?ll=48.45141,10.86574&z=15&t=h
>
>73
>Peter, DJ7WW
>
>
>
>-----Original Message-----
>From: Topband [mailto:topband-bounces at contesting.com] On Behalf Of Chuck
>Sent: Dienstag, 5. Februar 2013 08:28
>To: topband at 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=0.026507,0.05574
>7&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 at 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=0.026507,0.05574
>7&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 at msn.com>
>>> Subject: New 160M high performance receiving antenna at W3LPL
>>> To: "Robert McGwier" <rwmcgwier at gmail.com>, "Frank Donovan"
><donovanf at starpower.net>
>>> Cc: "Topband" <topband at 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
>>>
>>>
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>> Topband Reflector
>>
>>
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