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I got to thinking about other approaches to this problem. I took another look at a design that I use when I go car camping(my version of a caravan). It uses a couple of bent, folded dipole antennas, made out of 1/2" copper plumbing pipe and soldered joints, connected together with a couple of balun, equal length coax, and a splitter/combiner. I know that my actual gain will be at least .5db below what the model shows, because of the combiner and cable. I just assume that my losses will be about 1db. The two loops are held on a PVC frame, that comes apart and allows me to carry them in the car. I leave the cables attached, so it's easy to assemble and put up. I've modeled a version with reflectors, that greatly improves the HiVHF band, but haven't added the reflectors to my setup. I just use the two loops. AGT adjustment is close enough, for HiVHF and UHF, that you can get pretty good results displaying both band together. The design works very well in the US Repack band, but displays a bit of excessive SWR and Impedance mismatch above 675mhz. Maybe a little more work, and that can be resolved. Otherwise, your going to see some issues on those last few upper UHF channels.

Code:
CM Design began with HiVHF+UHF, VEE Stick Dipole, Variable ANGLE, 4nec2 by holl_ands, 27Jul2014
CM Stacked 2 elements
CM Adjusted for Australian band    HiVHF 174-230mhz           UHF  526-694mhz
CM Combine with 4:1 balun and equal length coax connected to 75ohm splitter/combiner  (Expect about 1/2db additional loss due to combiner).
CM All elements 5/8-in Copper (1/2" plumbing tubing and joints)
CM Folded forward 45 degrees (use 90 degree elbow)
CM Sides are 90 degree elbows and tee.
CM ALL MEASUREMENTS IN INCHES.
CM Char. Impedance = 300-ohm.  AGT=1.0
CM Modeled without autoseg.
CM Folding forward 45 degrees gives better UHF results and Reflectors improve Hi-VHF results
CE
SY Rsrc=0.319    'Simulated SOURCE Wire Radius, Adjust for AGT=1.0: UHF(610)=0.310,   HiVHF(202)=0.328
SY Scale=1.0
SY sc=Scale
SY Relem=0.3125    'Radius of Elements (1/2" copper tubing actual diameter is 5/8")
SY Rrefl=0.125    'Radius of Reflector (1/4" rods)
SY DipoleHeight=3.1875    'Distance between Folded Dipole Elements
SY dh=DipoleHeight    'Distance between Folded Dipole Elements
SY gap=3.0    'Center Gap Size between Elements
SY Rlen0=52.0    'Center Reflector length
SY Rlen1=33.25    'Inner Reflector length
SY Rback0=15.0    'Outer Reflector back from element
SY Rback1=11.0    'Inner Reflector back from element
SY Rseperation=20.0    'Reflector Seperation betweet outer reflectors
SY Rsep=Rseperation/2    'Reflector Seperation
SY len=14.6875    'Total Length of Folded Dipole Element:    15.1875" for US Repack band
SY Angle=90    'Sweep Angle between element legs (For Straight Dipole set Angle=0.0):
SY ang2=Angle/2    'Swept Forward Angle away from Y-Axis (For Straight Dipole set Angle=0.0):
SY wingDx=len*sin(ang2)    'Wing end location X axis
SY wingDy=len*cos(ang2)    'Wing end location Y axis
SY gapDy=gap/2    'Gap end location Y axis
SY gapDx=gapDy*tan(ang2)    'Gap end location X axis
SY Eseperation=24.0    'Seperation of element Feed Point    25.875     25.0
SY Esep=Eseperation/2    'Seperation of element Feed Point from center
SY Hseperation=88.0    'Seperation of element Feed Point    88.0
SY hsep=Hseperation/2    'Seperation of element Feed Point from center
GW    2    5    gapDx*sc    gapDy*sc    Esep*sc    wingDx*sc    wingDy*sc    Esep*sc    Relem
GW    3    5    gapDx*sc    -gapDy*sc    Esep*sc    wingDx*sc    -wingDy*sc    Esep*sc    Relem
GW    4    5    gapDx*sc    gapDy*sc    (Esep+dh)*sc    wingDx*sc    wingDy*sc    (Esep+dh)*sc    Relem
GW    45    1    gapDx*sc    gapDy*sc    (Esep+dh)*sc    0    0    (Esep+dh)*sc    Relem
GW    5    5    gapDx*sc    -gapDy*sc    (Esep+dh)*sc    wingDx*sc    -wingDy*sc    (Esep+dh)*sc    Relem
GW    55    1    gapDx*sc    -gapDy*sc    (Esep+dh)*sc    0    0    (Esep+dh)*sc    Relem
GW    6    1    wingDx*sc    wingDy*sc    Esep*sc    wingDx*sc    wingDy*sc    (Esep+dh)*sc    Relem
GW    7    1    wingDx*sc    -wingDy*sc    Esep*sc    wingDx*sc    -wingDy*sc    (Esep+dh)*sc    Relem
GW    23    19    -Rback1*sc    -Rlen1/2*sc    (Esep+(dh/2))*sc    -Rback1*sc    Rlen1/2*sc    (Esep+(dh/2))*sc    Rrefl
GX    800    001
GW    41    19    -Rback0*sc    -Rlen0/2*sc    0    -Rback0*sc    Rlen0/2*sc    0    Rrefl
GW    990    3    gapDx*sc    -gapDy*sc    Esep*sc    gapDx*sc    gapDy*sc    Esep*sc    Rsrc    'SOURCE
GW    991    3    gapDx*sc    -gapDy*sc    -Esep*sc    gapDx*sc    gapDy*sc    -Esep*sc    Rsrc    'SOURCE
GS    0    0    0.0254
GE    0
LD    5    0    0    0    58000000    'Copper Elements
GN    -1
EK
EX    0    990    2    0    1    0    0
EX    0    991    2    0    1    0    0
FR    0    45    0    0    174    12
RP    0    1    73    1510    90    0    1    5    0    0
EN
Frame for the reflectors could be left unglued, and fold up as well. This may give you another option. It doesn't have a much gain, as the 2 bay bowtie, but has more gain than your 1bay, and the parts fold up and store pretty easy. Photos are my antenna, without reflectors. You can remove the reflectors, from the model, and recalculate, to get results.
folded Copper Loop 58 front.JPG
folded Copper Loop 58 cabling.JPG
folded Copper Loop 58 packed.JPG
folded Copper Loop 58 screws.JPG


Let me know if you have any questions.
 

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Discussion Starter #42
Hi Lawrence
I tried to improve the AGT by reducing the source wire radius and changing the feed separation from 1in to .5in.
Got AGT 1.239 .93db in red for 520mhz.
I assume you have to go into the editor/ freq/grd and change the freq , then run AGT again for different freq's.
Got 200mhz AGT 1.4 and 600mhz 1.26
Looks like my model maybe not too accurate in the Hi vhf range.
I read that no mater what you set the segments to in you line code. The auto segment will set it's own number of segments per wire.
In the 3D window, the segments seem to the same size in all the wires.
I may have to accept the low impedance figures for the Hi vhf band 127 ohms at 210mhz.
I managed to fit a rod reflector set back at 15in and obtained a extra 3db uhf and 2db Hi vhf gain.
I am also trying to model a single 4 whisker bowtie with some 10mm aluminum rod i have lying around, but 4nec2 keeps giving my wire too thick or tight bend errors.
Any idea of how to get around the errors or do you ignore them.
 

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Discussion Starter #43
Just seen your bent folded dipoles.
Nice work.
I don't have a means to silver solder. Last time i silver soldered i borrowed a butane burner to extend the column on my vodka still.
Can you receive the Hi vhf by bending the folded dipole. I though dipoles where narrow band.
Like flaring a dipole into a bowtie gives wider bandwith.
How did you get 4nec2 to accept your 1/2 in copper pipe.
 

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I assume you have to go into the editor/ freq/grd and change the freq , then run AGT again for different freq's.
You can select the "Far Field pattern" and change the freq in the box on the right side of that screen. Since your going to be running the AGT test a number of times, it's easier to select the Freq/Ground screen, in the edit window, and change the start freq, to the freq you want to test AGT for. Then you won't have to change the freq, each time you run the AGT test. Remember to change the freq back, to the correct start frequency, before you run the model. I've learned to test AGT at the center of my freq range, while I'm trying/testing thing, and then check the low, mid, and high freq before I run final test, on a design. Usually the closer the radius required for AGT=1.0, for all frequencies your interested in, the more stable the antenna design. Some designs require a very different radius for HiVHF and UHF. These designs will require different runs for HiVHF and UHF, with the correct radius set for each freq range. Many designs require different segments for HiVHF runs and UHF runs as well. If you know Linux and Python programming, you can run some of Nikiml's scripts, to automate some of the design functions, and also see raw vs actual gain figures and how close the AGT figure is to 1.0 at each frequency in a range(I haven't learned that yet, so any questions will have to be directed to someone like MajorTom.

I am also trying to model a single 4 whisker bowtie with some 10mm aluminum rod i have lying around, but 4nec2 keeps giving my wire too thick or tight bend errors.
Most people have just ignored the warnings for 4 whisker bowties(two whiskers going left and two whiskers going right). Holl_and modeled some six whisker bowties, and was having problems AGT to work. He created a tri-connect bowtie, that he felt worked better. Click on UHF Bowties - NO Reflector to see his models. Adding in more whiskers will require additional connectors, to get them to work properly. I think some of the models that Lassar has posted, with multiple whiskers on each side, are not getting accurate results, because of the very shallow angles and multiple whiskers. Overall I think it's best not to ignore warnings.

I may have to accept the low impedance figures for the Hi vhf band 127 ohms at 210mhz.
If you look at other HiVHF/UHF designs, you will see that this is a common problem. Sometimes it can be resolved, by spacing or length of reflectors, but not always. As I said earlier, it makes more difference if you have long cable runs, from your antenna to your receiver. Maybe someone will correct me, but I think using an amplifier near the antenna actually helps, by effectively correcting the impedance match of the amplifier signal, before the signal is sent to the receiver.
 

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How did you get 4nec2 to accept your 1/2 in copper pipe.
Many people feel that my models may not be accurate, with such thick wires. I've learned that any design, that uses very short elements, becomes questionable. I usually have to manually segment the model, to get it to work. Yurii has modeled a couple of my designs, using different modeling software, and his results weren't that much different from mine using 4nec2. I'm willing to accept that my models might not be giving perfect results, but I've found that 4nec2 does allow me to design antennas, using 1/2" copper tubing(actually 5/8" diameter), that works very well. I've got access to some scrap tubing and joints, and have the tools to solder, so it's an easy build method for me.


Can you receive the Hi vhf by bending the folded dipole. I though dipoles where narrow band.
Holl_and had a design Hi-VHF+UHF "VEE" Stick Dipole that bent single dipole elements forward to cover the HiVHF and UHF band. I got to wondering if it would work with a folded dipole, so I modeled it. I'd seen HiVHF dipoles made from 1/2" tubing, so I modeled it, and found that folding it forward 45 degrees on each side(uses 90 degree elbow), and it worked for HiVHF as well as UHF.

If soldering the joints won't work for you, you might consider modeling it with 1/4" copper tubing. 1/4" copper tubing can be bent into pretty tight bends, without collapsing or breaking. The end bends can be done as one radius, going from the top to the bottom wire. The 90 degree bend, to provide the forward bend, should be as tight as possible, without collapsing the tubing. Bending 1/4" tubing isn't as easy as you would think, but I don't think you will need a super tight bend. My model allows you to select other angles of forward sweep/bend, and you might find something other than 90 degrees work better. With the solder joints, I'm limited to sweep angles of 45 and 90 degrees(only common fittings available). The soldered joints are close enough to a "perfect" corner, so I don't model it with multiple wires. Your bends, with 1/4" tubing won't be as sharp, and may need to be modeled with a couple of shorter segments simulating the radius. Be aware that you will start to get warnings and errors, if you use too short of wires.

One thing that I like about the 1/2" tubing, is that it is bomb proof. It takes a lot of bouncing around, in the car, without getting deformed. 1/4" tubing will require more careful storage.
 

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Discussion Starter #46
I loaded your bent folded dipole model with and without reflector.
Your gains where better than i an getting.
I do have a 1/4 in pipe bender. Just need some soft drawn copper tube.
Not sure if the bender radius would be small enough to bend the 3.2 in end of the dipole end.

I already have 2mm copper wire thought the enclosed bowtie maybe a little more durable than open bowtie.
Enough PVC water pipe, elbows and tees to make a couple of antennas.
There are so many designs to ponder over. I don't need a lot of gain as i will be using a LNA with 30db gain.
Just needs to be compact and robust.
One concern is in a caravan park environment with a lot of aluminum cladded caravans around me, a reflector would help block reflected signal that cause multi path signals and poor signal quality
Thanks for your help. I'm still getting to know 4nec2 software and antenna design.
But enjoying the learning curve.
 

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Discussion Starter #47
Hi Lawrence.
I was hoping you could help me to get my AGT closer to 1 for my antenna.
I have tried to adjust the source wire dia and fiddled with segmenting but can't get it very close to 1.
My raw gain figures do look a little too high.
 

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I assume that your still working on the model in post #39. I'll look at it again. What frequencies are you having luck with, and what frequencies are you struggling with?

Your design, in post #39 may be a very good design, but it has a couple of issues, that make it difficult to model with 4nec2. 4nec2 doesn't give accurate results if the volume of two connected wire segments overlap more than 1/3 of the length of either segment. This is usually an issue if you have very tight angles, very thick wires, or very short segments. This is what causes the "too sharp angle or too short/thick segment" error. Often you have to make compromises, to limit these issues.

4nec2 was designed to model antennas, that are made of relatively thin wire elements. You can attempt to model solid "sheet metal" elements, with an array of interconnected wires, and usually you get reasonable results. It's often difficult to know what the best shape, for the elements in the array should be.

Your design requires us to model the interaction of a thin wire(the loop) with a flat surface(the bowtie). In reality this is a wire spaced very close to a flat surface. Any way that you model it, in 4nec2, you have thin wires interacting with thin wires. I'm not sure that 4nec2 is up to the task. It may give us usable data, but may never give truly accurate results. What I'm not sure about is how the wires in the bowtie, should be oriented, related to the wire that forms the loop. My first impulse would be to run a wire in the bowtie, that runs parallel to the wire in the loop. I don't think this will work well, because 4nec2 doesn't handle closely spaced parallel wire very well. Next thought would be to have wires crossing at random angles. This is probably the easiest model to create, but may or may not give accurate results. My best guess would be to model the portion of the bowtie, near the loop, as a ladder shape, with the rungs crossing the loop at right angles, at equal intervals, and the uprights of the ladder being parallel to the loop, but far enough away from the loop, so that it models correctly. That all sound good, but it will be a complicated model to create. Even this may or may not create a valid model, and give accurate results.

All of that said, I'd guess that the only way that we will know, if we are getting accurate results, is to create a number of different models, using different patterns of wire placement, and see if we get similar results, from a variety of models. If we get similar results, I'd feel that we are getting adequate results. If we are getting very different results, from the different models, then I'd say the model isn't going to work well with 4nec2.

A while back I tried solid bowties with a closely spaced loop. The loop was outside the bowties, but spaced very close to the end of the bowtie. I could never get the AGT to work very well. I could get it to =1.0 at the center of the UHF band, but it was way off at the lower and upper end of the band. If I adjusted for the lower end of the band, it was way off at the middle and top of the band. I'm not sure if it was a problem with the design, or with 4nec2, but I finally gave up, and went back to standard bowties made of two whiskers. I don't think it was a problem with the design. I just think it wasn't a design that could be modeled easily in 4nec2.

I'll look at your design, over the next few days, and see what I can come up with.

Lawrence
 

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ljhavener,
I thought I posted this yesterday, but I guess not, as was still sitting here in the Post dialog when I returned this eve....
I was just eyeballing your folded dipole model above (Post 41 I think it was?). Looks pretty good to me.
I think an easier way to scale an antenna is to scale it at the GS card rather than scaling each wire individually.

What i generally try to do is something like this...
SY Fscale = Fold/Fnew

....
...
...
GS 0 0 0.0254*Fscale

The GS card will then scale all dimensions as per your Frequency Scale symbol.
Any element dimensions you do not want to scale, such as a GAP dimension of some sort that may be sensitive
to a characteristic impedance, you can then simply divide rather than multiply them one or two dimensions,
so it basically cancels out when the GS card is run. All other dimensions will be scaled when the GS card is run.
In your model I tried scaling by Fscale=681/700 MHz to shift the UHF high end swr a little higher, and the low end vhf swr a little lower. Seemed not bad... But still might need some work up around 750 to 800 MHz in the Australia UHF band, unless there is some pending changes going on in that spectrum? Not hip to what goes on in Australia.
 

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Majortom
Thanks for the suggestion on scaling, using the gs card. I've scaled antennas by calculating a new custom scale factor and entering it edit window/GS card. I didn't think about creating a symbol, and entering it into the scale window. I started using my method, because I could never remember how much I had scaled by, and got tired of having to recalculate it. Using the symbol will work just as well. I've gotten used to adding a scale factor, to my model, from the very beginning. It does give you a lot of control, over what elements get scaled, and which ones don't. I've gotten used to it, and like how easy it is, to see what items I'm scaling and what I'm not scaling. Your method will definitely be easier to use on someone else's model.

But still might need some work up around 750 to 800 MHz in the Australia UHF band
In Australia we are using VHf band 3 174-230 MHZ and UHF band 4 and 5 526 to 694 MHZ.
Grey Nomad indicated that they need UHF from 526 to 694, so that is what I tried to optimize the design for. He mentioned that, at any given location, all of his signals will be coming from the same tower, and that he often parks near other metal skinned campers. My design is not very directional, so it may not be a very good choice, for his purpose. I live in rural Colorado, and often an trying to get signals from a number of towers, from all different directions. I look for camping locations where the altitude gives me views to towers from a variety of directions and distances. Many of our towers have a very limited number of channels, so even though I may be getting signals from as many as 8 or 10 towers, I rarely have conflicting signals, on the same frequency. This little antenna packs easily in my car(camper), sets up easily, and picks up signals from many directions. Cover the US Repack very well, but it was stretching it, to get it to work with the Australian bands. Here's the US Repack version.
Code:
CM Design began with HiVHF+UHF, VEE Stick Dipole, Variable ANGLE, 4nec2 by holl_ands, 27Jul2014
CM Stacked 2 elements
CM Added reflectors to improve HiVHF
CM Combined with baluns, equal length coax, and a splitter/combiner.  Probably losing close to 1db due to cabling and combiner.
CM All elements 5/8-in Copper (1/2" plumbing tubing and joints)
CM Folded forward 45 degrees (use 90 degree elbow)
CM Sides are 90 degree elbows
CM ALL MEASUREMENTS IN INCHES.
CM Char. Impedance = 300-ohm.  AGT=1.0
CM Modeled without autoseg.
CM Folding forward 45 degrees gives better UHF results and Reflectors improve Hi-VHF results
CM Design is modular and can be used with all reflectors, just the inner and outer reflector or just the two elements.  You can even use just one element, or one element and the reflector behind it, without changing any dimensions.
CE
SY Rsrc=0.321    'Simulated SOURCE Wire Radius, Adjust for AGT=1.0: UHF(533)=0.316,   HiVHF(198)=0.326
SY Scale=1.0
SY sc=Scale
SY Relem=0.3125    'Radius of Elements (1/2" copper tubing actual diameter is 5/8")
SY Rrefl=0.3125    'Radius of Reflector (1/2" copper tubing actual diameter is 5/8")
SY DipoleHeight=3.1875    'Distance between Folded Dipole Elements
SY dh=DipoleHeight    'Distance between Folded Dipole Elements
SY gap=3.0    'Center Gap Size between Elements
SY Rlen0=52.0    'Center Reflector length    52.0
SY Rlen1=33.25    'Inner Reflector length   28.75    32.0    33.25
SY Rback0=15.0    'Outer Reflector back from element    15.0
SY Rback1=11.0    'Inner Reflector back from element      11.0
SY Rseperation=20.0    'Reflector Seperation betweet outer reflectors
SY Rsep=Rseperation/2    'Reflector Seperation
SY len=15.1875    'Total Length of Folded Dipole Element:
SY Angle=90    'Sweep Angle between element legs (For Straight Dipole set Angle=0.0):
SY ang2=Angle/2    'Swept Forward Angle away from Y-Axis (For Straight Dipole set Angle=0.0):
SY wingDx=len*sin(ang2)    'Wing end location X axis
SY wingDy=len*cos(ang2)    'Wing end location Y axis
SY gapDy=gap/2    'Gap end location Y axis
SY gapDx=gapDy*tan(ang2)    'Gap end location X axis
SY Eseperation=24.0    'Seperation of element Feed Point    25.875     25.0
SY Esep=Eseperation/2    'Seperation of element Feed Point from center
SY Hseperation=88.0    'Seperation of element Feed Point    88.0
SY hsep=Hseperation/2    'Seperation of element Feed Point from center
GW    2    7    gapDx*sc    gapDy*sc    Esep*sc    wingDx*sc    wingDy*sc    Esep*sc    Relem
GW    3    7    gapDx*sc    -gapDy*sc    Esep*sc    wingDx*sc    -wingDy*sc    Esep*sc    Relem
GW    4    7    gapDx*sc    gapDy*sc    (Esep+dh)*sc    wingDx*sc    wingDy*sc    (Esep+dh)*sc    Relem
GW    45    1    gapDx*sc    gapDy*sc    (Esep+dh)*sc    0    0    (Esep+dh)*sc    Relem
GW    5    7    gapDx*sc    -gapDy*sc    (Esep+dh)*sc    wingDx*sc    -wingDy*sc    (Esep+dh)*sc    Relem
GW    55    1    gapDx*sc    -gapDy*sc    (Esep+dh)*sc    0    0    (Esep+dh)*sc    Relem
GW    6    1    wingDx*sc    wingDy*sc    Esep*sc    wingDx*sc    wingDy*sc    (Esep+dh)*sc    Relem
GW    7    1    wingDx*sc    -wingDy*sc    Esep*sc    wingDx*sc    -wingDy*sc    (Esep+dh)*sc    Relem
GW    23    19    -Rback1*sc    -Rlen1/2*sc    (Esep+(dh/2))*sc    -Rback1*sc    Rlen1/2*sc    (Esep+(dh/2))*sc    Rrefl
GX    800    001
GW    41    19    -Rback0*sc    -Rlen0/2*sc    0    -Rback0*sc    Rlen0/2*sc    0    Rrefl
GW    990    3    gapDx*sc    -gapDy*sc    Esep*sc    gapDx*sc    gapDy*sc    Esep*sc    Rsrc    'SOURCE
GW    991    3    gapDx*sc    -gapDy*sc    -Esep*sc    gapDx*sc    gapDy*sc    -Esep*sc    Rsrc    'SOURCE
GS    0    0    0.0254
GE    0
LD    5    0    0    0    58000000    'Copper Elements
GN    -1
EK
EX    0    990    2    0    1    0    0
EX    0    991    2    0    1    0    0
FR    0    39    0    0    174    12
RP    0    1    73    1510    90    0    1    5    0    0
EN
 

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Discussion Starter #51
Hi Lawrence
Yes the antenna I'm referring to is in post 39.
I am getting better AGT figures in the UHF band. AGT 1.163 but in the VHF band AGT shows a red figure AGT 1.58.
Even tried wire tapering either side of the source wire but couldn't workout the two radius values.
I have reduced the source wire size to the smallest that 4nec2 will accept, so will stick with that
and build it and see how it performs.
The wire size I'm using is only 2mm Dia. That's the largest single strand i could find besides using multi strand wire.

When i catch up with a aircon installer mate i will see if he has recovered 1/4 copper pipe, so i can try to make your folded dipole or a Wildwillie's Hi-VHF+UHF Dreamcatcher bowtie in loop antenna.
Thank again
Emmanuel
 

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I built this, and it’s fantastic! It gets all the same channels as my M4. It looked like a good design, but I was pleasantly surprised. The VHF gain is a bit lower, but UHF might be a bit higher.

I used 14AWG copper for the phase lines instead of sheet metal. I cut out four aluminum triangles, screwed the copper directly into them, and put it all on a PVC frame.
 

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Hi
I modeled your antenna, from post #39, using a higher resolution bowtie(modeled more wires), to see what results we could get. Was able to get AGT to =1.0, so it may give us better results. I'm still not sure that 4nec2 is going to model a solid bowtie, located so close to a wire(the zig-zag loop), very accurately, but this is my best attempt.

Modeled using autoSeg(15). AGT differs quite a bit from the lower end, to the upper end, of the HiVHF and the UHF bands. You will want to model the HiVHF and the UHF bands seperately. I listed the source wire radius for the center of each band. You will want to look a the AGT numbers, for the lower and upper frequency of each band, to see how far the results are off, when modeled using the AGT numbers, for the center of the band. I put this model together pretty quickly, so you will want to look it over to make sure it's got your dimensions correct, and doesn't have any errrors.

Code:
CM UHF Solid Triangle 1-Bay Bowtie, 33-Wires, NO Refl, 4nec2 by holl_ands, 20Jun2013
CE
SY Rsrc=0.034    'SOURCE wire Radius. Adjust for AGT=1.0:          AutoSeg(15)    UHF(610)=0.034       HiVHF(202)=0.060
SY Rbow=0.051    'Radius (in inches) of BOWTIE elements
SY RACT=0.051
SY Rfeed=0.0625    'FEEDLINE wire Radius
SY Rstub=(Rfeed+Rbow)/2    'Feed Stub to transition to bowtie
SY FedSep=1.0    'Separation (in inches) between two FEEDLINE wires
SY BowSep=6.25    'Bow Tine Separation     6.25
SY bzs=BowSep/20    'Bow Tine Separation segments
SY BowLen=11.0    'Bow Length     11
SY bys=BowLen/10    'Bow Length Segment
SY feed=FedSep/2
SY H=14
SY W=16.25
SY Off=-0.3    'X-Coord. Separation Offset between 2-Bay and Loop
SY Cond=1.67e7    'Conductivity (Copper=3.0e7, Alum=2.0e7, StainlessSteel=1.67e7)
SY ib=0    'No offset, single bowtie
SY y11=feed+(1*bys)
SY y12=feed+(2*bys)
SY y13=feed+(3*bys)
SY y14=feed+(4*bys)
SY y15=feed+(5*bys)
SY y16=feed+(6*bys)
SY y17=feed+(7*bys)
SY y18=feed+(8*bys)
SY y19=feed+(9*bys)
SY yend=feed+BowLen
SY z11=1*bzs
SY z12=2*bzs
SY z13=3*bzs
SY z14=4*bzs
SY z15=5*bzs
SY z16=6*bzs
SY z17=7*bzs
SY z18=8*bzs
SY z19=9*bzs
SY z20=10*bzs
GW    1    3    0    feed    ib    0    y11    ib    Rstub
GW    2    3    0    y11    ib    0    y12    ib+z12    Rbow
GW    3    3    0    y11    ib    0    y12    ib-z12    Rbow
GW    4    3    0    y12    ib+z12    0    y12    ib-z12    Rbow
GW    5    3    0    y12    ib+z12    0    y13    ib    Rbow
GW    6    3    0    y12    ib-z12    0    y13    ib    Rbow
GW    7    3    0    y12    ib+z12    0    y13    ib+z13    Rbow
GW    8    3    0    y12    ib-z12    0    y13    ib-z13    Rbow
GW    9    3    0    y13    ib    0    y13    ib+z13    Rbow
GW    10    3    0    y13    ib    0    y13    ib-z13    Rbow
GW    11    3    0    y13    ib+z13    0    y14    ib    Rbow
GW    12    3    0    y13    ib-z13    0    y14    ib    Rbow
GW    13    3    0    y13    ib+z13    0    y14    ib+z14    Rbow
GW    14    3    0    y13    ib-z13    0    y14    ib-z14    Rbow
GW    15    3    0    y14    ib    0    y14    ib+z14    Rbow
GW    16    3    0    y14    ib    0    y14    ib-z14    Rbow
GW    17    3    0    y14    ib+z14    0    y15    ib    Rbow
GW    18    3    0    y14    ib-z14    0    y15    ib    Rbow
GW    19    3    0    y14    ib+z14    0    y15    ib+z15    Rbow
GW    20    3    0    y14    ib-z14    0    y15    ib-z15    Rbow
GW    21    3    0    y15    ib    0    y15    ib+z15    Rbow
GW    22    3    0    y15    ib    0    y15    ib-z15    Rbow
GW    23    3    0    y14    ib    0    y15    ib    Rbow
GW    24    3    0    y15    ib    0    y16    ib+z13    Rbow
GW    25    3    0    y15    ib    0    y16    ib-z13    Rbow
GW    26    3    0    y15    ib+z15    0    y16    ib+z13    Rbow
GW    27    3    0    y15    ib-z15    0    y16    ib-z13    Rbow
GW    28    3    0    y15    ib+z15    0    y16    ib+z16    Rbow
GW    29    3    0    y15    ib-z15    0    y16    ib-z16    Rbow
GW    30    3    0    y15    ib    0    y16    ib    Rbow
GW    31    3    0    y16    ib+z13    0    y16    ib+z16    Rbow
GW    32    3    0    y16    ib-z13    0    y16    ib-z16    Rbow
GW    33    1    0    y16    ib    0    y16    ib+z13    Rbow
GW    34    1    0    y16    ib    0    y16    ib-z13    Rbow
GW    35    3    0    y16    ib    0    y17    ib+z13    Rbow
GW    36    3    0    y16    ib    0    y17    ib-z13    Rbow
GW    37    3    0    y16    ib+z16    0    y17    ib+z13    Rbow
GW    38    3    0    y16    ib-z16    0    y17    ib-z13    Rbow
GW    39    3    0    y16    ib+z16    0    y17    ib+z17    Rbow
GW    40    3    0    y16    ib-z16    0    y17    ib-z17    Rbow
GW    41    3    0    y16    ib    0    y17    ib    Rbow
GW    42    3    0    y16    ib+z13    0    y17    ib+z13    Rbow
GW    43    3    0    y16    ib-z13    0    y17    ib-z13    Rbow
GW    44    3    0    y17    ib+z13    0    y17    ib+z17    Rbow
GW    45    3    0    y17    ib-z13    0    y17    ib-z17    Rbow
GW    46    1    0    y17    ib    0    y17    ib+z13    Rbow
GW    47    1    0    y17    ib    0    y17    ib-z13    Rbow
GW    48    3    0    y17    ib+z13    0    y18    ib    Rbow
GW    49    3    0    y17    ib-z13    0    y18    ib    Rbow
GW    50    3    0    y17    ib+z17    0    y18    ib+z14    Rbow
GW    51    3    0    y17    ib-z17    0    y18    ib-z14    Rbow
GW    52    3    0    y17    ib+z17    0    y18    ib+z18    Rbow
GW    53    3    0    y17    ib-z17    0    y18    ib-z18    Rbow
GW    54    3    0    y17    ib    0    y18    ib    Rbow
GW    55    3    0    y17    ib+z13    0    y18    ib+z14    Rbow
GW    56    3    0    y17    ib-z13    0    y18    ib-z14    Rbow
GW    57    3    0    y18    ib+z14    0    y18    ib+z18    Rbow
GW    58    3    0    y18    ib-z14    0    y18    ib-z18    Rbow
GW    59    3    0    y18    ib    0    y18    ib+z14    Rbow
GW    60    3    0    y18    ib    0    y18    ib-z14    Rbow
GW    61    3    0    y18    ib    0    y19    ib+z14    Rbow
GW    62    3    0    y18    ib    0    y19    ib-z14    Rbow
GW    63    3    0    y18    ib+z18    0    y19    ib+z14    Rbow
GW    64    3    0    y18    ib-z18    0    y19    ib-z14    Rbow
GW    65    3    0    y18    ib+z18    0    y19    ib+z19    Rbow
GW    66    3    0    y18    ib-z18    0    y19    ib-z19    Rbow
GW    67    3    0    y18    ib    0    y19    ib    Rbow
GW    68    3    0    y18    ib+z14    0    y19    ib+z14    Rbow
GW    69    3    0    y18    ib-z14    0    y19    ib-z14    Rbow
GW    70    3    0    y19    ib+z14    0    y19    ib+z19    Rbow
GW    71    3    0    y19    ib-z14    0    y19    ib-z19    Rbow
GW    72    3    0    y19    ib    0    y19    ib+z14    Rbow
GW    73    3    0    y19    ib    0    y19    ib-z14    Rbow
GW    74    3    0    y19    ib+z14    0    yend    ib    Rbow
GW    75    3    0    y19    ib-z14    0    yend    ib    Rbow
GW    76    3    0    y19    ib+z14    0    yend    ib+z16    Rbow
GW    77    3    0    y19    ib-z14    0    yend    ib-z16    Rbow
GW    78    3    0    y19    ib+z19    0    yend    ib+z16    Rbow
GW    79    3    0    y19    ib-z19    0    yend    ib-z16    Rbow
GW    80    3    0    y19    ib+z19    0    yend    ib+z20    Rbow
GW    81    3    0    y19    ib-z19    0    yend    ib-z20    Rbow
GW    82    3    0    y19    ib    0    yend    ib    Rbow
GW    83    3    0    yend    ib    0    yend    ib+z16    Rbow
GW    84    3    0    yend    ib    0    yend    ib-z16    Rbow
GW    85    3    0    yend    ib+z16    0    yend    ib+z20    Rbow
GW    86    3    0    yend    ib-z16    0    yend    ib-z20    Rbow
GW    200    9    Off    0    H/2    Off    W/2    H/2    RACT    'Top
GW    201    9    Off    W/2    0    Off    W/6    H/4    RACT    'RT
GW    202    9    Off    W/2    0    Off    W/6    -H/4    RACT    'RB
GW    203    9    Off    W/2    -H/2    Off    0    -H/2    RACT    'RB
GW    204    9    Off    W/6    H/4    Off    W/2    H/2    RACT
GW    205    9    Off    W/2    -H/2    Off    W/6    -H/4    RACT
GX    900    010
GW    999    9    0    feed    0    0    -feed    0    Rsrc
GS    0    0    0.0254
GE    0
LD    5    0    0    0    Cond    'Conductivity
GN    -1
EK
EX    0    999    5    0    1    0    0    'GW1 is SOURCE wire
FR    0    31    0    0    526    6
RP    0    1    73    1510    90    0    1    5    0    0
EN
 
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