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#1
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antenna construction
I have the following represents my roof and the tree in my backyard.
The length of the roof is 90ft, it is 15ft from the center line to each edge, (roughly 30ft), height of roof is approx 22ft at the peak and 10ft at the gutter edge.. The tree is approximately 35ft high. xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx x O x x x x ----------------------------------------------------x x x xxxxxxxxxx x O x x x xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx x O x x x xxxxxxxxxx TREE My question is: do you think it would be better to run a configuration as say a Windom from the tree to the points on the roof (the points can be moved) or just a simple inverted "V" and the angle of the "V" in any case is going to be very narrow. I would be feeding either one via some Rg8x approximately 65ft. I would like to be able to use the ant from 160m - 6m if possible, I will be feeding it via a tuner, and the wire is going to be #26 enameled as it can't be seen. Comments please. 73's Howard W3CQH |
#2
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antenna construction
Sorry for the repost - I was trying to get the visual dimensions correct!
The following represents my roof and the tree in my backyard. The length of the roof is 90ft, it is 15ft from the center line to each edge, (roughly 30ft), height of roof is approx 22ft at the peak and 10ft at the gutter edge.. The tree is approximately 35ft high. xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx x O x x x x ---------------------------------------------------x x x xxxxxxxxxx x O x x x xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx x O x x x xxxxxxxxxx TREE My question is: do you think it would be better to run a configuration as say a Windom from the tree to the points on the roof (the points can be moved) or just a simple inverted "V" and the angle of the "V" in any case is going to be very narrow. I would be feeding either one via some Rg8x approximately 65ft. I would like to be able to use the ant from 160m - 6m if possible, I will be feeding it via a tuner, and the wire is going to be #26 enameled as it can't be seen. Comments please. 73's Howard W3CQH |
#3
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antenna construction
Sorry for the repost - I was trying to get the visual dimensions correct! The following represents my roof and the tree in my backyard. The length of the roof is 90ft, it is 15ft from the center line to each edge, (roughly 30ft), height of roof is approx 22ft at the peak and 10ft at the gutter edge.. The tree is approximately 35ft high. xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx x O x x x x ---------------------------------------------------x x x xxxxx x O x x O x xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxx TREE My question is: do you think it would be better to run a configuration as say a Windom from the tree to the points on the roof (the points can be moved) or just a simple inverted "V" and the angle of the "V" in any case is going to be very narrow. I would be feeding either one via some Rg8x approximately 65ft. I would like to be able to use the ant from 160m - 6m if possible, I will be feeding it via a tuner, and the wire is going to be #26 enameled as it can't be seen. Comments please. 73's Howard W3CQH |
#4
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antenna construction
"W3CQH" wrote in message . .. Sorry for the repost - I was trying to get the visual dimensions correct! The following represents my roof and the tree in my backyard. The length of the roof is 90ft, it is 15ft from the center line to each edge, (roughly 30ft), height of roof is approx 22ft at the peak and 10ft at the gutter edge.. The tree is approximately 35ft high. xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx x O x x x x -------------------------------------------x x x xxxxx x O x x O x xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxx TREE My question is: do you think it would be better to run a configuration as say a Windom from the tree to the points on the roof (the points can be moved) or just a simple inverted "V" and the angle of the "V" in any case is going to be very narrow. I would be feeding either one via some Rg8x approximately 65ft. I would like to be able to use the ant from 160m - 6m if possible, I will be feeding it via a tuner, and the wire is going to be #26 enameled as it can't be seen. Comments please. 73's Howard W3CQH |
#5
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antenna construction
W3CQH wrote:
"W3CQH" wrote in message . .. Sorry for the repost - I was trying to get the visual dimensions correct! The following represents my roof and the tree in my backyard. The length of the roof is 90ft, it is 15ft from the center line to each edge, (roughly 30ft), height of roof is approx 22ft at the peak and 10ft at the gutter edge.. The tree is approximately 35ft high. xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx x O x x x x -------------------------------------------x x x xxxxx x O x x O x xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxx TREE My question is: do you think it would be better to run a configuration as say a Windom from the tree to the points on the roof (the points can be moved) or just a simple inverted "V" and the angle of the "V" in any case is going to be very narrow. I would be feeding either one via some Rg8x approximately 65ft. I would like to be able to use the ant from 160m - 6m if possible, I will be feeding it via a tuner, and the wire is going to be #26 enameled as it can't be seen. Comments please. Guess I'll reply to this one! ;^) How much total length will you have? A Windom for 160 needs 260 feet. I used a windom for a while because it was convenient, the short leg dropped the coax directly down to my shack window. The antenna performed okay. Depending on your lot size, you might not be able to run a full 160 meter version. would 80 meters be an okay bottom limit? Even if you had to let the ends drop a bit, though tuning (short vs long leg) will be a little different. Inverted v might also be a little difficult. You might want to go for a plain dipole. I'm pretty dense today - getting over a nasty head cold, so I'm going to ask a few questions. You just have the one tree? If so, where are you planning to hang the other end of the dipole. Certainly an inverted V is going to need something in the middle. With the tree at 35 feet, what is the maximum height you can hang a wire at? It doesn't sound like a real optimum site, but don't worry, we can get you something that will work okay. - 73 de Mike N3LI - |
#6
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antenna construction
Just some thoughts...
That #26 wire is going to be a problem no matter what type antenna you end up with. For the longer antennas, HF, etc, it's strength is going to be sort of limiting. It is sort of difficult to see, but it's far from being invisible. So, if you are in one of 'those' neighborhoods that don't like 'visible' antennas there is another choice instead of an invisible antenna. That's using something that is very visible, but not normally associated with antennas. The first thing that comes to mind is a flag pole. Certainly 'do-able', and certainly not going to be 'simple' if it covers more than one 'chunk' of HF. The 'simple' way of 'curing' that sort of thingy is to throw money at it, to some ridiculous point. (Wonder how 'they'ed feel about a 'commemorative' Atlas missile monument in your yard?) I think you might do some thinking about what's the longest, sort of straight, 'run' you can manage using the roof ridge and tree. A few 'bends' in that 'straight' run are allowable, sort of. And then consider various ways of 'loading' that run. One option might be a 'short' but 'long' inverted 'L', a "lazy-L"? Not exactly the best, has it's own set of 'problems', but if it works, who cares...much. Having 'been there, done that' at at one time or another, I really wish you luck. - 'Doc |
#7
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antenna construction
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#8
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antenna construction
"Cecil Moore" wrote in message ... wrote: The first thing that comes to mind is a flag pole. A 22' flagpole (with buried radials) can be base-fed with an SG-230 (for instance) to achieve reasonable performance on 40m-10m. -- 73, Cecil http://www.w5dxp.com I used one of those for several years in a "restricted" neighborhood. Performance was not bad. I used a manually switched coil/capacitor combination mounted at the base in a wooden box obtained from the local beekeeper supply house. While the box was a little large, it was inexpensive, and held up well in weather with a new paint job every 2-3 years. |
#9
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antenna construction
wrote in message ... Just some thoughts... That #26 wire is going to be a problem no matter what type antenna you end up with. For the longer antennas, HF, etc, it's strength is going to be sort of limiting. It is sort of difficult to see, but it's far from being invisible. So, if you are in one of 'those' neighborhoods that don't like 'visible' antennas there is another choice instead of an invisible antenna. That's using something that is very visible, but not normally associated with antennas. The first thing that comes to mind is a flag pole. Certainly 'do-able', and certainly not going to be 'simple' if it covers more than one 'chunk' of HF. The 'simple' way of 'curing' that sort of thingy is to throw money at it, to some ridiculous point. (Wonder how 'they'd feel about a 'commemorative' Atlas missile monument in your yard?) I think you might do some thinking about what's the longest, sort of straight, 'run' you can manage using the roof ridge and tree. A few 'bends' in that 'straight' run are allowable, sort of. And then consider various ways of 'loading' that run. One option might be a 'short' but 'long' inverted 'L', a "lazy-L"? Not exactly the best, has it's own set of 'problems', but if it works, who cares...much. Having 'been there, done that' at one time or another, I really wish you luck. - 'Doc Thanks for your thoughts - I am NOT allowed either of the 2 items that you suggested (flag pole or missile - although I would like to have a Gatling Gun mounted and take pot shots at the senior citizens that use my street as a tune up for drag racing). 1] In my current configuration I have a #13ga jacketed wire coming out of a Icom A4 auto- tuner (which is in the attic next to the vent window). From the tuner, it goes up about 3 feet to the roof peak, makes a 90 degree turn and then traverses down the edge (15ft) to make a 90 degree turn down to the end of the roof (90ft) running along each of the gutters sides (but actual on the roof). Then it makes another 90 degree turn and goes up and over the peak to the other side of the roof, about (30ft) and makes another 90 degree turn and comes back (90ft) turns back up to the peak (15ft) and back down to the ground side of the tuner. I am hearing a lot of sigs, but I am having probs being heard! 100w! 2] Before I had this configuration, it was basically the same, except the auto-tuner wasn't in line, instead I was using a manual tuner. I had the same configuration on the roof, and an additional 2 runs (LOOPS) of the same size wire inside of the attic, total length of approximately 540ft. It was working (80-10), but I couldn't get it to tune to 160m. On the VHF/UHF frequencies, 6m thru 70cm it was working as a multi-wavelength RHOMBIC. I was able to work a bunch more stations, but still I thought I wanted more. But the problem is that the outside portion - the signals being transmitted - that the roof was probably absorbing most of them. 3] Whether I use a manual or auto tuner, I am trying to get the best configuration other laying the wire on the roof or stringing it along the rafters in the attic. The distance is approximately 20 feet from the tree to the house. I can bury a piece of coax from the house to the tree, and then run it up the tree to a center connection for a dipole, but the arms of the dipole are going to have to be bent into a "V" and terminate at some point along the longest sides of the roof just above the gutters. 4] As you suggested, I could run a dipole (using more of the #13ga wire, the ends facing N/S) along the ridge line and center or off-center feed it with coax, but then again, it will be laying on the roof. (90ft straight ridge line). 73's |
#10
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antenna construction
"Cecil Moore" wrote in message ... wrote: The first thing that comes to mind is a flag pole. A 22' flagpole (with buried radials) can be base-fed with an SG-230 (for instance) to achieve reasonable performance on 40m-10m. -- 73, Cecil http://www.w5dxp.com Thanks Cecil, but I can't have any flag poles. 73's |
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