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Locked The Geomantic Spiral
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Gents...
I have built my first geomantic (ground-coupled) antenna which I am calling the Geomantic Spiral. It's nothing more than 30' of RG58 coax rolled into a tight, flat spiral and placed on the ground under some bricks on my lanai (patio to you Mainland folk). Performance is _very_ good!!! I have posted a more detailed description and preliminary listening results in my new group at... <> Drop in and check it out. Everyone is welcome. 'Bear' NH7SR (Doing happy Snoopy dance) |
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Michael Stevenson
开云体育Hi Bear,
Just joined the group and checked out your early
results of the new geomantic Spiral antenna, very interesting stuff. When you
are ready you will have to give a photo and more detailed construction notes,
could be a nice antenna to play with (after I finish the 14 foot loop of
course!)
Nice new group Bear and hope it does well for
you!
Best regards!
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Michael Stevenson,
Australia.
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Michael,
Thanks for joining. I have set you to unmoderated so you can post at will. I don't have a camera at present so there won't be any photos for the time being. I'll see if I can whip together some kind of drawing. I haven't done any kind of analysis yet as to the why and how the Geomantic Spiral works. Looks like a promising area for experimentation and learning. I'll still be hanging around here, of course. Got lots of loop ideas I want to play with also. BTW, if the signal I'm receiving on 3.925 MHz from NHK Tokyo right now is any indication this hy'ar animule may turn out to be a very good Tropical Band antenna. 73, 'Bear' NH7SR --- In loopantennas@..., "Michael Stevenson" <portstevos@t...> wrote: Hi Bear,geomantic Spiral antenna, very interesting stuff. When you are ready you will have to give a photo and more detailed construction notes, could be a nice antenna to play with (after I finish the 14 foot loop of course!) Nice new group Bear and hope it does well for you!am calling the Geomantic Spiral. It's nothing more than 30' of RG58coax rolled into a tight, flat spiral and placed on the ground undersome bricks on my lanai (patio to you Mainland folk).listening results in my new group at...---------- Yahoo! Groups LinksService. |
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Michael Stevenson
开云体育Sound's great and will certainly have to give it a
go after my loop is upon it's final mounting. What is your QTH area like
Bear?
Is it flat or are you in a valley or hollow or are
you on top of a hill or on the side of a hill?
Any trees or buildings around close
by?
Thanks for the reply and best regards!
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Michael.
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Michael,
My QTH is a typical(?) urban environment. I live on the ground floor of a 3-story apartment building. My apartment is in the roughly NE corner. The ground elevation here is about 10' above sea level (I'm in a tidal wave inundation area). There is a large 25 story building only 50' to the North of me and several other tall buildings surrounding me within a 1/4 mile radius. I am also surrounded on all sides by elevated electrical, telephone and cable TV lines within a radius of 100 to 200'. There is a small park next to my building on the East and Southeast side. Perhaps 1 acre or a little less in area. There are a couple of very large, old Ficus trees growing there as well as some other smaller trees. My lanai area is only about 8' wide by 20' long. There is a Mock Orange hedge some 8' tall between me and the park. My 23' vertical antenna is located at the NE corner of the building and is only 2' from the side of the building. The lower section of it is 18" away from a 6' high chain-link fence. There are 3 elevated 24' radials connected to it as well as 1 24' buried radial. My loop antenna is on the roof of the apartment house and connected through a 100' RG-58 cable run. Currently the loop is acting intermittently. I think I have a loose connection up there that I will need to fix. The Geomantic Spiral is under the bricks in the barbeque area of the lanai about 3' from the side of the building. This is obviously not a "dream" DX location!! Despite that I have been able to make some pretty decent contacts with QRP operation on the 30 and 20 meter ham bands around the Pacific and into South America while running only 2 watts output. The plus side to this location is that it provides me the opportunity to play with and develop various types of antennas that will be effective in a "less than ideal" kind of environment. 73, 'Bear' NH7SR --- In loopantennas@..., "Michael Stevenson" <portstevos@t...> wrote: Sound's great and will certainly have to give it a go after my loopis upon it's final mounting. What is your QTH area like Bear? Is it flat or are you in a valley or hollow or are you on top of ahill or on the side of a hill? Any trees or buildings around close by?at will. I don't have a camera at present so there won't be anyphotos for the time being. I'll see if I can whip together some kind ofand how the Geomantic Spiral works. Looks like a promising area forideas I want to play with also.right now is any indication this hy'ar animule may turn out to be avery good Tropical Band antenna.new geomantic Spiral antenna, very interesting stuff. When you areready you will have to give a photo and more detailed constructionnotes, could be a nice antenna to play with (after I finish the 14 footloop of course!)which I amRG58 coaxunder some---- ----------Terms of Service.---------- Yahoo! Groups LinksService. |
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Michael Stevenson
开云体育Thankyou Bear for the very detailed picture of your
QTH and surrounding area, let's hope you don't get a tidal wave. Perhaps being
so close to sea level helps connects your antennas or ground plains to the sea
itself, we all know how good the sea is (or large bodies of water) at being
terrific gound plains for transmitting and receiving HF signals, maybe this is
why the Geomantic Spiral works so well on the ground.
Would be interesting to hear about this fascinating
antenna at other different locations and altitudes (above or away from the sea).
I live close to the sea which is around 3 miles to the south east and my QTH
would be around one to two hundred feet above the sea. I wonder how this type of
antenna would work for someone living in the mountains?
Should be very interesting days ahead as this
antenna is developed and experimented with by more people.
Thanks again Bear and best regards!
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Michael Stevenson,
Australia. (Port Macquarie in the state of New
South Wales on the east coast of Australia.)
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