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RE: Multi band vertical vs home brew wire antennas
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by M1DYS on November 9, 2006
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This looks like a fascinating project, but as I said in my first post, the problem I have is the trees are all in the wrong place! They line the perimeter of my garden. Along the longest side I have a large silver birch which waves around like crazy in the slightest breeze so, any wire running past it would be chafed or snapped.
I understand that here are many ways of getting a wire up, but I just wondered how *generally* a wire performed compered to a vert?
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RE: Multi band vertical vs home brew wire antennas
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by WW5AA on November 9, 2006
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Robert,
I'll go with the loop also. Some good information at:
http://www.cebik.com/fdim/atl1.html
73, de Lindy
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RE: Multi band vertical vs home brew wire antennas
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by WW5AA on November 9, 2006
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Robert,
The problem with a ¼ wave vertical antennas is that no matter how many times it is said, people fall for the advertising and are disappointed when that antenna is stuck into the ground without lots and lots of radials. A better method is mounting it higher with tuned above ground radials, but still needing at least two radials per band and 4 or 5 is better. The second consideration is that an adequate installation may cause high levels of QRN or vertically polarized noise in an urban environment. This can be overcome however by use of a horizontal RX antenna which does not need to be a huge beverage. The key is simply enough capture area to present a good signal to noise ratio. If this RX antenna is properly set up it can become an NVIS TX antenna to fill in short range needs since the verticals low angle of take off degrades its close in effectiveness. But at last I ramble on as usual…..Have fun!
73, de Lindy
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RE: Multi band vertical vs home brew wire antennas
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by M1DYS on November 11, 2006
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Ok, I've had another look at my tree situation & I should be able to string out a wire but in a triangle shape not a square as in the 'loop Skywire'. Will this have any effect on its performance? Is length an issue & also what about height above ground. I reckon at a struggle I can get it 40' above ground.
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RE: Multi band vertical vs home brew wire antennas
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by N3OX on November 13, 2006
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A big triangle 40 feet in the air will be quite good. Triangle, square, funny trapezoid; shape doesn't really matter as long as it's a nice, open loop. It's worth the struggle to get it up that high, especially since the lower bands are going to be more active at this point in the sunspot cycle. Good luck!
73,
Dan
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RE: Multi band vertical vs home brew wire antennas
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by M1DYS on November 19, 2006
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Thanks for all of your advice.
I've decided to put up a Loop Skywire & will let you know in due course how it performs. Having read many positive reports on this & other sites I'm looking forward to finding out for myself if it's as good as they say...
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RE: Multi band vertical vs home brew wire antennas
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by N5PSI on November 30, 2006
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Hello Robert,
I live in a deed restricted neighborhood and was faced with the same questions you are. I decided to go with a vertical antenna. I built one for 40M from a 33' fiberglass telescoping pole and 14AWG wire. I currently have 56 radials varying in length from 20' to 35' buried just beneath the surface. I am surprised at how well this antenna works. It is mounted right next to a tree and shrubs. It extends up into the tree, which has an opening up the middle. It is painted cammo brown and blends in with the tree quite well. I know it's not the ideal location but it's the best for me in order to hide it. A power transformer sits about 5' away and a nearby fence prevents me from having the radials 360 degrees around the antenna. I have made it through pileups with this antenna including VK9CGG, ZL8R, VQ9LA, and 5A1A just to name a few. Here are two pictures of the antenna:
http://s88848699.onlinehome.us/vert2.jpg
http://s88848699.onlinehome.us/vert3.jpg
I have recently built coaxial traps and added 30M capability to the antenna. Again, it works quite well for both 30 and 40M. I have another wire with a 20M trap for 20/40M operation. It is easy to lower the pole and switch elements. It doesn't work as well for 20M but it is acceptable. I did experiment with using 3 traps to give me 18M, 20M, 30M and 40M use but the loading effect of the traps shortened the antenna to around 18'. It worked but I know the losses were high so I am just using one trap.
When the higher bands get better during the upcoming sunspot cycle rise, I am going to experiment with vertical 1/2 wave dipoles using the telescoping pole.
73, Mike - N5PSI
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RE: Multi band vertical vs home brew wire antennas
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by N5PSI on December 1, 2006
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Thanks N3OX.
It's coincidence that you reply. I happened across your website on your "low band vertical" just the other day.
(http://www.n3ox.net/projects/lowbandvert)
I like your design and am considering doing something similar to give me 80M, 40M and 30M with no traps. I just don't think I could have the antenna extend beyond the top of my tree for 10' and not be noticeable. (My tree is right at 30' tall).
I may experiment with building an 80 loading coil and place it at about 75% of the antenna height for a 33' long element. Then, I would build the matching networks for 40 and 30M to place at the base of the vertical.
73, Mike
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RE: Multi band vertical vs home brew wire antennas
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by KC2WI on December 9, 2006
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If you have 40x45 feet then you have about 60 feet diagonally. A G5RV lite (see www.radiowavz.com/html/g5rv.htm) is 67 feet. I have a couple of these and while not perfect, they work pretty well. See review on eHam.net.
Or if you sacrifice 80/75M, then a G5RV junior (51 feet) should fit and depending on your transmatch you can might get it to work on 75M.
Either of these you can buy for under $50, or build yourself for a few dollars, as opposed to hundreds for a vertical, and as pointed out you'll have to put in a good radial system to make a vertical work well.
The G5RV may not be a perfect antenna, but you can't buy or build anything less expensive that is so versatile and simple.
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