GH Contraptions 1 and 2

[astupidoldman]

Hello everyone. My first post.

This is a warning to all the new guys that follow: The Ottawa Downshift is not a new automatic transmission from Canada! Read all the posts regarding the DBGH 1 before you build, or you will end up with this:



It stands 8 feet tall and is 5 feet wide. Please, no critiques just yet. I just read all 828 posts and know what I did wrong. I have already disassembled it and have started rebuilding from scratch, but let me tell you the story of a half crazed man obsessed with getting over on Comcast. When I found the GPLv3 drawings, I was enamored. Now, I am a nurse who passes pills to little old ladies, but when I was a kid I built a short wave radio. Surely, I thought, that would qualify me. I am only into 60 bucks for the 75 feet of copper ground wire from Lowes. Everything else I had on hand. My goal was not to go over one month’s bill for cable from Comcast. I started with just marking off 7 inch section and bending wire by hand. The original single mast in the center was the first phase. Everything was eyeballed, not measured and it worked. Not well, but as good as any bent up rabbit ears. I couldn’t believe the pictures were so clear. Little did I know that it was just the benefit digital TV and I was just picking up channels that were close. Then I went nuts. Bigger is always better. I immediately built the three masts side by side. The width was decided by how much lumber I had. The idea was to connect three DBGH’s together using the center of the phasing lines as the focal point and rotating them around that point.



Because of the spacing, the two outside driven elements had to overlap.



I found an old X-large folding dog kennel that soon became the 8’x5’ reflector. Then a whole roll of aluminum foil over that adhered in the back by duct tape. You can see the out line of the wire mesh in the foil. I ran to the TV, sweating and breathing hard. It had only taken two days to do. I hit search and to my dismay, reception was worse. I stood there staring at the monster in my living room(no, I’m not married), sweat now dripping down off my brow. My kids, visiting for the weekend, were secretly texting my ex that they thought daddy had flipped out. I suddenly flashed back to Richard Dryfess in Close Encounters of the Third Kind, standing there, staring at a mountain of mud in his living room.

After reading all 628 posts in this thread…I am better now. No really, I am. But like I said, ask me about resolving constipation issues in a 100 year old women, not radio theory. I drew up a template for the driven elements. I wasn’t even close. Maybe +/- 25 mm and none of which are the same length. The reflector is +/-10 mm, not flat. Element gaps, +/- 50 mm. Phasing lines are not the same lengths either. Spacing on the phasing lines must be +/- 150 mm.

I am just glad I didn’t start working on my idea for using fractals. So, it will be nice just getting back to a single mast as I now believe a multi-bay will be of little or no benefit. I have downloaded the modeling software and I will pursue that idea. I love using software to try and crash XP. Not only will I work on the multi bay modeling, but have every intention of using fractals. After looking at Cohen’s patent’s, I think there may be a way to around those and add to the DBGH.

I hope you guys get a good laugh out of this as it seems like some of you deserve it for all the work you have put in. Yes, I will read the DBGH II thread, the using the modeling software thread, OTA antenna design links before I build anything after rebuilding my DBGH.

Matt

[stampeder]

You're a good sport, Matt, and its nice to have a chuckle with you.

[mlord]

Ha! Good fun, that! And thank-you ever so much for the photos, too!!

Cheers from another Lynnwood: a suburb of Ottawa, Ontario, Canada!
And home to, not only myself but.., the great "G" of the SBGH antenna design!
(he lives about 3 houses up the street from me).

Cheer

[300ohm]

Thats one heck of a contraption, heh. All that wire can be re-straightened and reused using DogT's method of straightening wire.

I am just glad I didn’t start working on my idea for using fractals. So, it will be nice just getting back to a single mast as I now believe a multi-bay will be of little or no benefit. I have downloaded the modeling software and I will pursue that idea. I love using software to try and crash XP. Not only will I work on the multi bay modeling, but have every intention of using fractals. After looking at Cohen’s patent’s, I think there may be a way to around those and add to the DBGH.

There are fractal example models included in the 4nec2 software. Unfortunately, they dont have very much gain, which is the name of the game. I was also thinking of turning the GH into a simple fractal. It has to be kept simple, because think of all the exact bending that will be need to be done when building it. Using copper clad pcb for a fractal wi-fi antenna is very practical, but at UHF frequencies the cost of a large copper clad pcb is very expensive.

[astupidoldman]

That was a lot of fun. So now it’s rebuilt to spec’s. I am on the top floor of some apartments. I had used my zip at tvfool which looked really promising. But I only got four channels @ 50% consistently. Not my fave four channels either. So I warmed up the GPS and gave tvfool coordinates. This is what I have with a drawing of the exterior walls of the surrounding apartments. So I’m baked on that upper left quad inside the apartment. The solution is a 12 foot treated piece of wood, C-clamped to the railing on my deck. That will put a DBGH just above the chimneystacks coming up from the apartments directly below me. Not sure if it’ll clear the apex of the roofline, but I believe I may not need a rotor. The next build is a lightweight 12 foot portable mast. I only watch the boob tube when the kids are here anyway. I’d have to leave the mast down inside the apartment to keep the landlord from having a seizure. Also, I’d like to strap it to my Jeep. Up where I fly fish around here, it would be interesting to see how many channels LOS at those elevations. See if we couldn’t watch a little digital when we camped. I’ll be ready for the big Feb transition. I have to reboot my Asus motherboard that I usually use for editing video and then I’ll see what I can come up with on that modeling.

[300ohm]

So now it’s rebuilt to spec’s.

From your strong signals, it looks like you should be fine with just SBGH aimed at 355 degrees true, if you clear the other rooftops.

[astupidoldman]

Works great!

[300ohm]

Works great!

Im sure the antenna does, but not your picture posting skills, heh.

Just use the "direct link" at photobucket and paste it into the "Insert Image" icon in the posting.

[jjkroell]

I put mine together with 10AWG copper wire. I just found an old military antenna ( straight copper wire) that is about 3/16". What would be the benefit of changing the wire out?

[300ohm]

I put mine together with 10AWG copper wire. I just found an old military antenna ( straight copper wire) that is about 3/16". What would be the benefit of changing the wire out?

Performance wise, little to nothing. Durability wise, a lot.

Hows it performing for you ? Post a picture.


@ astupidoldman

Nice workmanship. I personally wouldnt have used wood, and I would turn the ubolts around. But your signals per TVFool are so strong, and a DBGH is such overkill, it doesnt make any difference with your digital signals.

Ive come to realize that with digital signals that the difference between say 85% and 95% on the meter is pretty meaningless, unlike with analog where even a small increase in gain resulted in less snow. When my dropouts occur, its usually a big drop down to say 30% on the meter, and of course no picture, heh. A drop to 40% on the meter would also result in no picture.

[astupidoldman]

I'm not sure what numbers I put in to tvfool the first time, but this is better. The overlay of the apartments is the same.

So once I had the right ones, it made it a lot easier to find stations. Then you may notice the clear plastic clamped to the mast and the devining rod. It's a home made azmuth and I just losen the clamps a tad and rotate. At 195 degrees, I can pick up most of what I want. But at 230 degrrees is Fox and I wanted that for football. It just wasn't coming in as well 195. So I went for a walk. I am totally surrounded by trees and it's more than just getting up 16 feet. So at 195 You can see the upper bay of the DBGH.

Now at 230, I have a real problem.

That is only the top couple reflectors showing. The wood version is very heavy and I really shouldn't go any higher with it. The whole mast rotates on that trailer hitch to a horizontal position when the wind picks up. When I first put it up, we had a storm rolling through with a steady 20 mph and gusts to 50. That would be the limit as it did put a bend in those fence posts. So now I am working toward contraption III. I'll build on PVC pipe and build for the ultra light. Contraption II will work for now until it's built. The wooden frame will be used like a jig for contraption III. Now that I have a working GH, I can take my time. Got my work horse Assus motherboard rebooted so I'll be modeling soon. I think I have the bug pretty bad. I got KVOS last night. 63 miles away and steady. Can't even get that on cable. This is fun or at least it will hold me over until I get out the river to fly fish next week.

[300ohm]

Then you may notice the clear plastic clamped to the mast and the devining rod. It's a home made azmuth and I just losen the clamps a tad and rotate.

Heh, I wondered what that was, I thought originally it was some kind of rain deflector. I use something very similiar, a piece of cardboard from the bottom of an old pizza package with a hole in the middle and a slit, and the direction markings. Then I just slide it on the mast, align to North, and I know where everything is.

I am totally surrounded by trees and it's more than just getting up 16 feet.

On a positive note, a lot of those leaves will soon fall, and reception will get better. The Pine/Fir trees however will still be a major problem blocking the signal. The leaves on my neighbors maples in front of one of my antennas have mostly fallen, and I can notice the consistant reception improvement. (Odd that their maple leaves always fall much sooner than the one in my yard, even though they are the exact same variety of maple, ie seeded from my tree)

When I first put it up, we had a storm rolling through with a steady 20 mph and gusts to 50. That would be the limit as it did put a bend in those fence posts.

Wow. I think those flat metal reflectors are catching a lot of the wind.

[astupidoldman]

NEC: NO SEGMENT HAS AN ITAG OF 1

I tried to generate this, but that is what I got as a response.

CM SBGH Gen2 GH10 Collinear Rod reflectors
CM perverted into a single mast quad
CM by astupidoldman
CE
GW 2 10 0 0.09025 -0.02675 0 0.23875 0.12175 3.5e-3
GW 3 10 0 0.23875 0.12175 0 0.09025 0.27025 3.5e-3
GW 4 10 0 0.09025 0.27025 0 0.23875 0.41875 3.5e-3
GW 5 10 0 0.23875 0.41875 0 0.32425 0.41875 3.5e-3
GW 6 10 0 0.09025 -0.02675 0 0.23875 -0.17525 3.5e-3
GW 7 10 0 0.23875 -0.17525 0 0.09025 -0.32375 3.5e-3
GW 8 10 0 0.09025 -0.32375 0 0.23875 -0.47225 3.5e-3
GW 9 10 0 0.23875 -0.47225 0 0.32425 -0.47225 3.5e-3
GW 10 10 0 -0.09975 -0.02675 0 -0.24825 0.12175 3.5e-3
GW 11 10 0 -0.24825 0.12175 0 -0.09975 0.27025 3.5e-3
GW 12 10 0 -0.09975 0.27025 0 -0.24825 0.41875 3.5e-3
GW 13 10 0 -0.24825 0.41875 0 -0.33375 0.41875 3.5e-3
GW 14 10 0 -0.09975 -0.02675 0 -0.24825 -0.17525 3.5e-3
GW 15 10 0 -0.24825 -0.17525 0 -0.09975 -0.32375 3.5e-3
GW 16 10 0 -0.09975 -0.32375 0 -0.24825 -0.47225 3.5e-3
GW 17 10 0 -0.24825 -0.47225 0 -0.33375 -0.47225 3.5e-3
GW 18 18 -0.0855 0.27425 -0.695 -0.0855 0.06775 -0.695 3.5e-3
GW 19 18 -0.0855 -0.28375 -0.695 -0.0855 -0.07725 -0.695 3.5e-3
GW 22 18 -0.0855 0.40475 -0.5465 -0.0855 0.06775 -0.5465 3.5e-3
GW 23 18 -0.0855 -0.41425 -0.5465 -0.0855 -0.07725 -0.5465 3.5e-3
GW 30 18 -0.0855 0.51875 -0.398 -0.0855 0.06775 -0.398 3.5e-3
GW 31 18 -0.0855 -0.52825 -0.398 -0.0855 -0.07725 -0.398 3.5e-3
GW 38 18 -0.0855 0.31175 -0.2495 -0.0855 0.06775 -0.2495 3.5e-3
GW 39 18 -0.0855 -0.32125 -0.2495 -0.0855 -0.07725 -0.2495 3.5e-3
GW 46 18 -0.0855 0.42475 -0.101 -0.0855 0.06775 -0.101 3.5e-3
GW 47 18 -0.0855 -0.43425 -0.101 -0.0855 -0.07725 -0.101 3.5e-3
GW 52 18 -0.0855 0.42475 0.0475 -0.0855 0.06775 0.0475 3.5e-3
GW 53 18 -0.0855 -0.43425 0.0475 -0.0855 -0.07725 0.0475 3.5e-3
GW 60 18 -0.0855 0.31175 0.196 -0.0855 0.06775 0.196 3.5e-3
GW 61 18 -0.0855 -0.32125 0.196 -0.0855 -0.07725 0.196 3.5e-3
GW 68 18 -0.0855 0.51875 0.3445 -0.0855 0.06775 0.3445 3.5e-3
GW 69 18 -0.0855 -0.52825 0.3445 -0.0855 -0.07725 0.3445 3.5e-3
GW 76 18 -0.0855 0.40475 0.493 -0.0855 0.06775 0.493 3.5e-3
GW 77 18 -0.0855 -0.41425 0.493 -0.0855 -0.07725 0.493 3.5e-3
GW 80 18 -0.0855 0.27425 0.6415 -0.0855 0.06775 0.6415 3.5e-3
GW 81 18 -0.0855 -0.28375 0.6415 -0.0855 -0.07725 0.6415 3.5e-3
GW 83 10 0 0.08925 1.42 0 0.23775 1.5685 3.5e-3
GW 84 10 0 0.23775 1.5685 0 0.08925 1.717 3.5e-3
GW 85 10 0 0.08925 1.717 0 0.23775 1.8655 3.5e-3
GW 86 10 0 0.23775 1.8655 0 0.32325 1.8655 3.5e-3
GW 87 10 0 0.08925 1.42 0 0.23775 1.2715 3.5e-3
GW 88 10 0 0.23775 1.2715 0 0.08925 1.123 3.5e-3
GW 89 10 0 0.08925 1.123 0 0.23775 0.9745 3.5e-3
GW 90 10 0 0.23775 0.9745 0 0.32325 0.9745 3.5e-3
GW 91 10 0 -0.10075 1.42 0 -0.24925 1.5685 3.5e-3
GW 92 10 0 -0.24925 1.5685 0 -0.10075 1.717 3.5e-3
GW 93 10 0 -0.10075 1.717 0 -0.24925 1.8655 3.5e-3
GW 94 10 0 -0.24925 1.8655 0 -0.33475 1.8655 3.5e-3
GW 95 10 0 -0.10075 1.42 0 -0.24925 1.2715 3.5e-3
GW 96 10 0 -0.24925 1.2715 0 -0.10075 1.123 3.5e-3
GW 97 10 0 -0.10075 1.123 0 -0.24925 0.9745 3.5e-3
GW 98 10 0 -0.24925 0.9745 0 -0.33475 0.9745 3.5e-3
GW 99 18 -0.0855 0.27325 0.75175 -0.0855 0.06675 0.75175 3.5e-3
GW 100 18 -0.0855 -0.28475 0.75175 -0.0855 -0.07825 0.75175 3.5e-3
GW 101 18 -0.0855 0.40375 0.90025 -0.0855 0.06675 0.90025 3.5e-3
GW 102 18 -0.0855 -0.41525 0.90025 -0.0855 -0.07825 0.90025 3.5e-3
GW 103 18 -0.0855 0.51775 1.04875 -0.0855 0.06675 1.04875 3.5e-3
GW 104 18 -0.0855 -0.52925 1.04875 -0.0855 -0.07825 1.04875 3.5e-3
GW 105 18 -0.0855 0.31075 1.19725 -0.0855 0.06675 1.19725 3.5e-3
GW 106 18 -0.0855 -0.32225 1.19725 -0.0855 -0.07825 1.19725 3.5e-3
GW 107 18 -0.0855 0.42375 1.34575 -0.0855 0.06675 1.34575 3.5e-3
GW 108 18 -0.0855 -0.43525 1.34575 -0.0855 -0.07825 1.34575 3.5e-3
GW 109 18 -0.0855 0.42375 1.49425 -0.0855 0.06675 1.49425 3.5e-3
GW 110 18 -0.0855 -0.43525 1.49425 -0.0855 -0.07825 1.49425 3.5e-3
GW 111 18 -0.0855 0.31075 1.64275 -0.0855 0.06675 1.64275 3.5e-3
GW 112 18 -0.0855 -0.32225 1.64275 -0.0855 -0.07825 1.64275 3.5e-3
GW 113 18 -0.0855 0.51775 1.79125 -0.0855 0.06675 1.79125 3.5e-3
GW 114 18 -0.0855 -0.52925 1.79125 -0.0855 -0.07825 1.79125 3.5e-3
GW 115 18 -0.0855 0.40375 1.93975 -0.0855 0.06675 1.93975 3.5e-3
GW 116 18 -0.0855 -0.41525 1.93975 -0.0855 -0.07825 1.93975 3.5e-3
GW 117 18 -0.0855 0.27325 2.08825 -0.0855 0.06675 2.08825 3.5e-3
GW 118 18 -0.0855 -0.28475 2.08825 -0.0855 -0.07825 2.08825 3.5e-3
GW 121 5 0 -0.09975 -0.02675 0 -0.05475 -0.02675 3.5e-3
GW 122 5 0 0.04525 -0.02675 0 0.09025 -0.02675 3.5e-3
GW 123 5 0 -0.10075 1.42 0 -0.05575 1.42 3.5e-3
GW 124 5 0 0.04425 1.42 0 0.08925 1.42 3.5e-3
GW 125 61 0 -0.05475 -0.02675 0 -0.05525 0.696625 3.5e-3
GW 209 61 0 -0.05525 0.696625 0 -0.05575 1.42 3.5e-3
GW 126 61 0 0.04525 -0.02675 0 0.04475 0.696625 3.5e-3
GW 210 61 0 0.04475 0.696625 0 0.04425 1.42 3.5e-3
GW 127 10 0 0.09075 2.88 0 0.23925 3.0285 3.5e-3
GW 128 10 0 0.23925 3.0285 0 0.09075 3.177 3.5e-3
GW 129 10 0 0.09075 3.177 0 0.23925 3.3255 3.5e-3
GW 130 10 0 0.23925 3.3255 0 0.32475 3.3255 3.5e-3
GW 131 10 0 0.09075 2.88 0 0.23925 2.7315 3.5e-3
GW 132 10 0 0.23925 2.7315 0 0.09075 2.583 3.5e-3
GW 133 10 0 0.09075 2.583 0 0.23925 2.4345 3.5e-3
GW 134 10 0 0.23925 2.4345 0 0.32475 2.4345 3.5e-3
GW 135 10 0 -0.09925 2.88 0 -0.24775 3.0285 3.5e-3
GW 136 10 0 -0.24775 3.0285 0 -0.09925 3.177 3.5e-3
GW 137 10 0 -0.09925 3.177 0 -0.24775 3.3255 3.5e-3
GW 138 10 0 -0.24775 3.3255 0 -0.33325 3.3255 3.5e-3
GW 139 10 0 -0.09925 2.88 0 -0.24775 2.7315 3.5e-3
GW 140 10 0 -0.24775 2.7315 0 -0.09925 2.583 3.5e-3
GW 141 10 0 -0.09925 2.583 0 -0.24775 2.4345 3.5e-3
GW 142 10 0 -0.24775 2.4345 0 -0.33325 2.4345 3.5e-3
GW 143 18 -0.0855 0.27475 2.21175 -0.0855 0.06825 2.21175 3.5e-3
GW 144 18 -0.0855 -0.28325 2.21175 -0.0855 -0.07675 2.21175 3.5e-3
GW 145 18 -0.0855 0.40525 2.36025 -0.0855 0.06825 2.36025 3.5e-3
GW 146 18 -0.0855 -0.41375 2.36025 -0.0855 -0.07675 2.36025 3.5e-3
GW 147 18 -0.0855 0.51925 2.50875 -0.0855 0.06825 2.50875 3.5e-3
GW 148 18 -0.0855 -0.52775 2.50875 -0.0855 -0.07675 2.50875 3.5e-3
GW 149 18 -0.0855 0.31225 2.65725 -0.0855 0.06825 2.65725 3.5e-3
GW 150 18 -0.0855 -0.32075 2.65725 -0.0855 -0.07675 2.65725 3.5e-3
GW 151 18 -0.0855 0.42525 2.80575 -0.0855 0.06825 2.80575 3.5e-3
GW 152 18 -0.0855 -0.43375 2.80575 -0.0855 -0.07675 2.80575 3.5e-3
GW 153 18 -0.0855 0.42525 2.95425 -0.0855 0.06825 2.95425 3.5e-3
GW 154 18 -0.0855 -0.43375 2.95425 -0.0855 -0.07675 2.95425 3.5e-3
GW 155 18 -0.0855 0.31225 3.10275 -0.0855 0.06825 3.10275 3.5e-3
GW 156 18 -0.0855 -0.32075 3.10275 -0.0855 -0.07675 3.10275 3.5e-3
GW 157 18 -0.0855 0.51925 3.25125 -0.0855 0.06825 3.25125 3.5e-3
GW 158 18 -0.0855 -0.52775 3.25125 -0.0855 -0.07675 3.25125 3.5e-3
GW 159 18 -0.0855 0.40525 3.39975 -0.0855 0.06825 3.39975 3.5e-3
GW 160 18 -0.0855 -0.41375 3.39975 -0.0855 -0.07675 3.39975 3.5e-3
GW 161 18 -0.0855 0.27475 3.54825 -0.0855 0.06825 3.54825 3.5e-3
GW 162 18 -0.0855 -0.28325 3.54825 -0.0855 -0.07675 3.54825 3.5e-3
GW 163 10 0 0.08975 4.32675 0 0.23825 4.47525 3.5e-3
GW 164 10 0 0.23825 4.47525 0 0.08975 4.62375 3.5e-3
GW 165 10 0 0.08975 4.62375 0 0.23825 4.77225 3.5e-3
GW 166 10 0 0.23825 4.77225 0 0.32375 4.77225 3.5e-3
GW 167 10 0 0.08975 4.32675 0 0.23825 4.17825 3.5e-3
GW 168 10 0 0.23825 4.17825 0 0.08975 4.02975 3.5e-3
GW 169 10 0 0.08975 4.02975 0 0.23825 3.88125 3.5e-3
GW 170 10 0 0.23825 3.88125 0 0.32375 3.88125 3.5e-3
GW 171 10 0 -0.10025 4.32675 0 -0.24875 4.47525 3.5e-3
GW 172 10 0 -0.24875 4.47525 0 -0.10025 4.62375 3.5e-3
GW 173 10 0 -0.10025 4.62375 0 -0.24875 4.77225 3.5e-3
GW 174 10 0 -0.24875 4.77225 0 -0.33425 4.77225 3.5e-3
GW 175 10 0 -0.10025 4.32675 0 -0.24875 4.17825 3.5e-3
GW 176 10 0 -0.24875 4.17825 0 -0.10025 4.02975 3.5e-3
GW 177 10 0 -0.10025 4.02975 0 -0.24875 3.88125 3.5e-3
GW 178 10 0 -0.24875 3.88125 0 -0.33425 3.88125 3.5e-3
GW 179 18 -0.0855 0.27375 3.6585 -0.0855 0.06725 3.6585 3.5e-3
GW 180 18 -0.0855 -0.28425 3.6585 -0.0855 -0.07775 3.6585 3.5e-3
GW 181 18 -0.0855 0.40425 3.807 -0.0855 0.06725 3.807 3.5e-3
GW 182 18 -0.0855 -0.41475 3.807 -0.0855 -0.07775 3.807 3.5e-3
GW 183 18 -0.0855 0.51825 3.9555 -0.0855 0.06725 3.9555 3.5e-3
GW 184 18 -0.0855 -0.52875 3.9555 -0.0855 -0.07775 3.9555 3.5e-3
GW 185 18 -0.0855 0.31125 4.104 -0.0855 0.06725 4.104 3.5e-3
GW 186 18 -0.0855 -0.32175 4.104 -0.0855 -0.07775 4.104 3.5e-3
GW 187 18 -0.0855 0.42425 4.2525 -0.0855 0.06725 4.2525 3.5e-3
GW 188 18 -0.0855 -0.43475 4.2525 -0.0855 -0.07775 4.2525 3.5e-3
GW 189 18 -0.0855 0.42425 4.401 -0.0855 0.06725 4.401 3.5e-3
GW 190 18 -0.0855 -0.43475 4.401 -0.0855 -0.07775 4.401 3.5e-3
GW 191 18 -0.0855 0.31125 4.5495 -0.0855 0.06725 4.5495 3.5e-3
GW 192 18 -0.0855 -0.32175 4.5495 -0.0855 -0.07775 4.5495 3.5e-3
GW 193 18 -0.0855 0.51825 4.698 -0.0855 0.06725 4.698 3.5e-3
GW 194 18 -0.0855 -0.52875 4.698 -0.0855 -0.07775 4.698 3.5e-3
GW 195 18 -0.0855 0.40425 4.8465 -0.0855 0.06725 4.8465 3.5e-3
GW 196 18 -0.0855 -0.41475 4.8465 -0.0855 -0.07775 4.8465 3.5e-3
GW 197 18 -0.0855 0.27375 4.995 -0.0855 0.06725 4.995 3.5e-3
GW 198 18 -0.0855 -0.28425 4.995 -0.0855 -0.07775 4.995 3.5e-3
GW 199 5 0 -0.09925 2.88 0 -0.05425 2.88 3.5e-3
GW 200 5 0 0.04575 2.88 0 0.09075 2.88 3.5e-3
GW 201 5 0 -0.10025 4.32675 0 -0.05525 4.32675 3.5e-3
GW 202 5 0 0.04475 4.32675 0 0.08975 4.32675 3.5e-3
GW 203 61 0 -0.05425 2.88 0 -0.05475 3.603375 3.5e-3
GW 206 61 0 -0.05475 3.603375 0 -0.05525 4.32675 3.5e-3
GW 204 61 0 0.04575 2.88 0 0.04525 3.603375 3.5e-3
GW 205 61 0 0.04525 3.603375 0 0.04475 4.32675 3.5e-3
GW 207 3 0 0.04525 3.603375 0 0.02025 3.603375 3.5e-3
GW 208 3 0 -0.02975 3.603375 0 -0.05475 3.603375 3.5e-3
GW 211 3 0 0.04475 0.696625 0 0.01975 0.696625 3.5e-3
GW 212 3 0 -0.05525 0.696625 0 -0.03025 0.696625 3.5e-3
GW 213 114 0 -0.02975 3.603375 0 -0.03 2.15 3.5e-3
GW 216 114 0 -0.03 2.15 0 -0.03025 0.696625 3.5e-3
GW 217 114 0 0.02025 3.603375 0 0.02 2.15 3.5e-3
GW 218 114 0 0.02 2.15 0 0.01975 0.696625 3.5e-3
GW 219 5 0 -0.03 2.15 0 0.02 2.15 3.5e-3
GE 0
EK
LD 5 0 0 0 2.49e7 0
EX 0 1 3 0 1 0
GN -1
FR 0 1 0 0 585 0


I have crashed my puter enough to get some measurements and this is what I'd like to build next. Catching up on everyones work they have done for the last year toward this project, has been an impossible task in the last week. So I haven't been able to generate anything of value from the modeling software. So I have no idea on net gains for this, but I certainly have enough copper as some of you may recall. I know you kind gentlemen are busy, but any help would be appreciated.

Matt

[300ohm]

NEC: NO SEGMENT HAS AN ITAG OF 1

I tried to generate this, but that is what I got as a response.

That message is actually pretty self explanatory, unlike a lot of the others, heh. You have no Tag (wire) 1. Your EX card, the loading point - ie where you connect the coax to, was defined on Tag (wire) 1, when it should have been on Tag 219. I also adjusted that loading wire to give an AGT of 1.0 (0db) by changing the wire radius from .1378 to .195. I added a RP card (Far Field Pattern) and changed the FR (Frequency) card so you can run a Raw Gain and SWR etc chart for the whole UHF range, starting at 473mhz, 6mhz step size, 40 steps. (dont panic and think your computer is locked up, it takes a loooong time to finish) Compare your old model to the new one and note the differences.


CM SBGH Gen2 GH10 Collinear Rod reflectors
CM perverted into a single mast quad
CM by astupidoldman
CE
GW 2 10 0 3.55314961 -1.0531496 0 9.3996063 4.79330709 0.13779528
GW 3 10 0 9.3996063 4.79330709 0 3.55314961 10.6397638 0.13779528
GW 4 10 0 3.55314961 10.6397638 0 9.3996063 16.4862205 0.13779528
GW 5 10 0 9.3996063 16.4862205 0 12.765748 16.4862205 0.13779528
GW 6 10 0 3.55314961 -1.0531496 0 9.3996063 -6.8996063 0.13779528
GW 7 10 0 9.3996063 -6.8996063 0 3.55314961 -12.746063 0.13779528
GW 8 10 0 3.55314961 -12.746063 0 9.3996063 -18.59252 0.13779528
GW 9 10 0 9.3996063 -18.59252 0 12.765748 -18.59252 0.13779528
GW 10 10 0 -3.9271654 -1.0531496 0 -9.773622 4.79330709 0.13779528
GW 11 10 0 -9.773622 4.79330709 0 -3.9271654 10.6397638 0.13779528
GW 12 10 0 -3.9271654 10.6397638 0 -9.773622 16.4862205 0.13779528
GW 13 10 0 -9.773622 16.4862205 0 -13.139764 16.4862205 0.13779528
GW 14 10 0 -3.9271654 -1.0531496 0 -9.773622 -6.8996063 0.13779528
GW 15 10 0 -9.773622 -6.8996063 0 -3.9271654 -12.746063 0.13779528
GW 16 10 0 -3.9271654 -12.746063 0 -9.773622 -18.59252 0.13779528
GW 17 10 0 -9.773622 -18.59252 0 -13.139764 -18.59252 0.13779528
GW 18 18 -3.366142 10.797244 -27.3622 -3.366142 2.6673228 -27.3622 0.1377953
GW 19 18 -3.366142 -11.17126 -27.3622 -3.366142 -3.041339 -27.3622 0.1377953
GW 22 18 -3.366142 15.935039 -21.51575 -3.366142 2.6673228 -21.51575 0.1377953
GW 23 18 -3.366142 -16.30906 -21.51575 -3.366142 -3.041339 -21.51575 0.1377953
GW 30 18 -3.366142 20.423228 -15.66929 -3.366142 2.6673228 -15.66929 0.1377953
GW 31 18 -3.366142 -20.79724 -15.66929 -3.366142 -3.041339 -15.66929 0.1377953
GW 38 18 -3.366142 12.273622 -9.822835 -3.366142 2.6673228 -9.822835 0.1377953
GW 39 18 -3.366142 -12.64764 -9.822835 -3.366142 -3.041339 -9.822835 0.1377953
GW 46 18 -3.366142 16.722441 -3.976378 -3.366142 2.6673228 -3.976378 0.1377953
GW 47 18 -3.366142 -17.09646 -3.976378 -3.366142 -3.041339 -3.976378 0.1377953
GW 52 18 -3.366142 16.722441 1.8700787 -3.366142 2.6673228 1.8700787 0.1377953
GW 53 18 -3.366142 -17.09646 1.8700787 -3.366142 -3.041339 1.8700787 0.1377953
GW 60 18 -3.366142 12.273622 7.7165354 -3.366142 2.6673228 7.7165354 0.1377953
GW 61 18 -3.366142 -12.64764 7.7165354 -3.366142 -3.041339 7.7165354 0.1377953
GW 68 18 -3.366142 20.423228 13.562992 -3.366142 2.6673228 13.562992 0.1377953
GW 69 18 -3.366142 -20.79724 13.562992 -3.366142 -3.041339 13.562992 0.1377953
GW 76 18 -3.366142 15.935039 19.409449 -3.366142 2.6673228 19.409449 0.1377953
GW 77 18 -3.366142 -16.30906 19.409449 -3.366142 -3.041339 19.409449 0.1377953
GW 80 18 -3.366142 10.797244 25.255906 -3.366142 2.6673228 25.255906 0.1377953
GW 81 18 -3.366142 -11.17126 25.255906 -3.366142 -3.041339 25.255906 0.1377953
GW 83 10 0 3.51377953 55.9055118 0 9.36023622 61.7519685 0.13779528
GW 84 10 0 9.36023622 61.7519685 0 3.51377953 67.5984252 0.13779528
GW 85 10 0 3.51377953 67.5984252 0 9.36023622 73.4448819 0.13779528
GW 86 10 0 9.36023622 73.4448819 0 12.726378 73.4448819 0.13779528
GW 87 10 0 3.51377953 55.9055118 0 9.36023622 50.0590551 0.13779528
GW 88 10 0 9.36023622 50.0590551 0 3.51377953 44.2125984 0.13779528
GW 89 10 0 3.51377953 44.2125984 0 9.36023622 38.3661417 0.13779528
GW 90 10 0 9.36023622 38.3661417 0 12.726378 38.3661417 0.13779528
GW 91 10 0 -3.9665354 55.9055118 0 -9.8129921 61.7519685 0.13779528
GW 92 10 0 -9.8129921 61.7519685 0 -3.9665354 67.5984252 0.13779528
GW 93 10 0 -3.9665354 67.5984252 0 -9.8129921 73.4448819 0.13779528
GW 94 10 0 -9.8129921 73.4448819 0 -13.179134 73.4448819 0.13779528
GW 95 10 0 -3.9665354 55.9055118 0 -9.8129921 50.0590551 0.13779528
GW 96 10 0 -9.8129921 50.0590551 0 -3.9665354 44.2125984 0.13779528
GW 97 10 0 -3.9665354 44.2125984 0 -9.8129921 38.3661417 0.13779528
GW 98 10 0 -9.8129921 38.3661417 0 -13.179134 38.3661417 0.13779528
GW 99 18 -3.366142 10.757874 29.596457 -3.366142 2.6279528 29.596457 0.1377953
GW 100 18 -3.366142 -11.21063 29.596457 -3.366142 -3.080709 29.596457 0.1377953
GW 101 18 -3.366142 15.895669 35.442913 -3.366142 2.6279528 35.442913 0.1377953
GW 102 18 -3.366142 -16.34843 35.442913 -3.366142 -3.080709 35.442913 0.1377953
GW 103 18 -3.366142 20.383858 41.28937 -3.366142 2.6279528 41.28937 0.1377953
GW 104 18 -3.366142 -20.83661 41.28937 -3.366142 -3.080709 41.28937 0.1377953
GW 105 18 -3.366142 12.234252 47.135827 -3.366142 2.6279528 47.135827 0.1377953
GW 106 18 -3.366142 -12.68701 47.135827 -3.366142 -3.080709 47.135827 0.1377953
GW 107 18 -3.366142 16.683071 52.982283 -3.366142 2.6279528 52.982283 0.1377953
GW 108 18 -3.366142 -17.13583 52.982283 -3.366142 -3.080709 52.982283 0.1377953
GW 109 18 -3.366142 16.683071 58.82874 -3.366142 2.6279528 58.82874 0.1377953
GW 110 18 -3.366142 -17.13583 58.82874 -3.366142 -3.080709 58.82874 0.1377953
GW 111 18 -3.366142 12.234252 64.675197 -3.366142 2.6279528 64.675197 0.1377953
GW 112 18 -3.366142 -12.68701 64.675197 -3.366142 -3.080709 64.675197 0.1377953
GW 113 18 -3.366142 20.383858 70.521654 -3.366142 2.6279528 70.521654 0.1377953
GW 114 18 -3.366142 -20.83661 70.521654 -3.366142 -3.080709 70.521654 0.1377953
GW 115 18 -3.366142 15.895669 76.36811 -3.366142 2.6279528 76.36811 0.1377953
GW 116 18 -3.366142 -16.34843 76.36811 -3.366142 -3.080709 76.36811 0.1377953
GW 117 18 -3.366142 10.757874 82.214567 -3.366142 2.6279528 82.214567 0.1377953
GW 118 18 -3.366142 -11.21063 82.214567 -3.366142 -3.080709 82.214567 0.1377953
GW 121 5 0 -3.9271654 -1.0531496 0 -2.1555118 -1.0531496 0.13779528
GW 122 5 0 1.78149606 -1.0531496 0 3.55314961 -1.0531496 0.13779528
GW 123 5 0 -3.9665354 55.9055118 0 -2.1948819 55.9055118 0.13779528
GW 124 5 0 1.74212598 55.9055118 0 3.51377953 55.9055118 0.13779528
GW 125 61 0 -2.1555118 -1.0531496 0 -2.1751969 27.4261811 0.13779528
GW 209 61 0 -2.1751969 27.4261811 0 -2.1948819 55.9055118 0.13779528
GW 126 61 0 1.78149606 -1.0531496 0 1.76181102 27.4261811 0.13779528
GW 210 61 0 1.76181102 27.4261811 0 1.74212598 55.9055118 0.13779528
GW 127 10 0 3.57283465 113.385827 0 9.41929134 119.232283 0.13779528
GW 128 10 0 9.41929134 119.232283 0 3.57283465 125.07874 0.13779528
GW 129 10 0 3.57283465 125.07874 0 9.41929134 130.925197 0.13779528
GW 130 10 0 9.41929134 130.925197 0 12.7854331 130.925197 0.13779528
GW 131 10 0 3.57283465 113.385827 0 9.41929134 107.53937 0.13779528
GW 132 10 0 9.41929134 107.53937 0 3.57283465 101.692913 0.13779528
GW 133 10 0 3.57283465 101.692913 0 9.41929134 95.8464567 0.13779528
GW 134 10 0 9.41929134 95.8464567 0 12.7854331 95.8464567 0.13779528
GW 135 10 0 -3.9074803 113.385827 0 -9.753937 119.232283 0.13779528
GW 136 10 0 -9.753937 119.232283 0 -3.9074803 125.07874 0.13779528
GW 137 10 0 -3.9074803 125.07874 0 -9.753937 130.925197 0.13779528
GW 138 10 0 -9.753937 130.925197 0 -13.120079 130.925197 0.13779528
GW 139 10 0 -3.9074803 113.385827 0 -9.753937 107.53937 0.13779528
GW 140 10 0 -9.753937 107.53937 0 -3.9074803 101.692913 0.13779528
GW 141 10 0 -3.9074803 101.692913 0 -9.753937 95.8464567 0.13779528
GW 142 10 0 -9.753937 95.8464567 0 -13.120079 95.8464567 0.13779528
GW 143 18 -3.366142 10.816929 87.076772 -3.366142 2.6870079 87.076772 0.1377953
GW 144 18 -3.366142 -11.15157 87.076772 -3.366142 -3.021654 87.076772 0.1377953
GW 145 18 -3.366142 15.954724 92.923228 -3.366142 2.6870079 92.923228 0.1377953
GW 146 18 -3.366142 -16.28937 92.923228 -3.366142 -3.021654 92.923228 0.1377953
GW 147 18 -3.366142 20.442913 98.769685 -3.366142 2.6870079 98.769685 0.1377953
GW 148 18 -3.366142 -20.77756 98.769685 -3.366142 -3.021654 98.769685 0.1377953
GW 149 18 -3.366142 12.293307 104.61614 -3.366142 2.6870079 104.61614 0.1377953
GW 150 18 -3.366142 -12.62795 104.61614 -3.366142 -3.021654 104.61614 0.1377953
GW 151 18 -3.366142 16.742126 110.4626 -3.366142 2.6870079 110.4626 0.1377953
GW 152 18 -3.366142 -17.07677 110.4626 -3.366142 -3.021654 110.4626 0.1377953
GW 153 18 -3.366142 16.742126 116.30906 -3.366142 2.6870079 116.30906 0.1377953
GW 154 18 -3.366142 -17.07677 116.30906 -3.366142 -3.021654 116.30906 0.1377953
GW 155 18 -3.366142 12.293307 122.15551 -3.366142 2.6870079 122.15551 0.1377953
GW 156 18 -3.366142 -12.62795 122.15551 -3.366142 -3.021654 122.15551 0.1377953
GW 157 18 -3.366142 20.442913 128.00197 -3.366142 2.6870079 128.00197 0.1377953
GW 158 18 -3.366142 -20.77756 128.00197 -3.366142 -3.021654 128.00197 0.1377953
GW 159 18 -3.366142 15.954724 133.84843 -3.366142 2.6870079 133.84843 0.1377953
GW 160 18 -3.366142 -16.28937 133.84843 -3.366142 -3.021654 133.84843 0.1377953
GW 161 18 -3.366142 10.816929 139.69488 -3.366142 2.6870079 139.69488 0.1377953
GW 162 18 -3.366142 -11.15157 139.69488 -3.366142 -3.021654 139.69488 0.1377953
GW 163 10 0 3.53346457 170.344488 0 9.37992126 176.190945 0.13779528
GW 164 10 0 9.37992126 176.190945 0 3.53346457 182.037402 0.13779528
GW 165 10 0 3.53346457 182.037402 0 9.37992126 187.883858 0.13779528
GW 166 10 0 9.37992126 187.883858 0 12.746063 187.883858 0.13779528
GW 167 10 0 3.53346457 170.344488 0 9.37992126 164.498031 0.13779528
GW 168 10 0 9.37992126 164.498031 0 3.53346457 158.651575 0.13779528
GW 169 10 0 3.53346457 158.651575 0 9.37992126 152.805118 0.13779528
GW 170 10 0 9.37992126 152.805118 0 12.746063 152.805118 0.13779528
GW 171 10 0 -3.9468504 170.344488 0 -9.7933071 176.190945 0.13779528
GW 172 10 0 -9.7933071 176.190945 0 -3.9468504 182.037402 0.13779528
GW 173 10 0 -3.9468504 182.037402 0 -9.7933071 187.883858 0.13779528
GW 174 10 0 -9.7933071 187.883858 0 -13.159449 187.883858 0.13779528
GW 175 10 0 -3.9468504 170.344488 0 -9.7933071 164.498031 0.13779528
GW 176 10 0 -9.7933071 164.498031 0 -3.9468504 158.651575 0.13779528
GW 177 10 0 -3.9468504 158.651575 0 -9.7933071 152.805118 0.13779528
GW 178 10 0 -9.7933071 152.805118 0 -13.159449 152.805118 0.13779528
GW 179 18 -3.366142 10.777559 144.03543 -3.366142 2.6476378 144.03543 0.1377953
GW 180 18 -3.366142 -11.19094 144.03543 -3.366142 -3.061024 144.03543 0.1377953
GW 181 18 -3.366142 15.915354 149.88189 -3.366142 2.6476378 149.88189 0.1377953
GW 182 18 -3.366142 -16.32874 149.88189 -3.366142 -3.061024 149.88189 0.1377953
GW 183 18 -3.366142 20.403543 155.72835 -3.366142 2.6476378 155.72835 0.1377953
GW 184 18 -3.366142 -20.81693 155.72835 -3.366142 -3.061024 155.72835 0.1377953
GW 185 18 -3.366142 12.253937 161.5748 -3.366142 2.6476378 161.5748 0.1377953
GW 186 18 -3.366142 -12.66732 161.5748 -3.366142 -3.061024 161.5748 0.1377953
GW 187 18 -3.366142 16.702756 167.42126 -3.366142 2.6476378 167.42126 0.1377953
GW 188 18 -3.366142 -17.11614 167.42126 -3.366142 -3.061024 167.42126 0.1377953
GW 189 18 -3.366142 16.702756 173.26772 -3.366142 2.6476378 173.26772 0.1377953
GW 190 18 -3.366142 -17.11614 173.26772 -3.366142 -3.061024 173.26772 0.1377953
GW 191 18 -3.366142 12.253937 179.11417 -3.366142 2.6476378 179.11417 0.1377953
GW 192 18 -3.366142 -12.66732 179.11417 -3.366142 -3.061024 179.11417 0.1377953
GW 193 18 -3.366142 20.403543 184.96063 -3.366142 2.6476378 184.96063 0.1377953
GW 194 18 -3.366142 -20.81693 184.96063 -3.366142 -3.061024 184.96063 0.1377953
GW 195 18 -3.366142 15.915354 190.80709 -3.366142 2.6476378 190.80709 0.1377953
GW 196 18 -3.366142 -16.32874 190.80709 -3.366142 -3.061024 190.80709 0.1377953
GW 197 18 -3.366142 10.777559 196.65354 -3.366142 2.6476378 196.65354 0.1377953
GW 198 18 -3.366142 -11.19094 196.65354 -3.366142 -3.061024 196.65354 0.1377953
GW 199 5 0 -3.9074803 113.385827 0 -2.1358268 113.385827 0.13779528
GW 200 5 0 1.8011811 113.385827 0 3.57283465 113.385827 0.13779528
GW 201 5 0 -3.9468504 170.344488 0 -2.1751969 170.344488 0.13779528
GW 202 5 0 1.76181102 170.344488 0 3.53346457 170.344488 0.13779528
GW 203 61 0 -2.1358268 113.385827 0 -2.1555118 141.865157 0.13779528
GW 206 61 0 -2.1555118 141.865157 0 -2.1751969 170.344488 0.13779528
GW 204 61 0 1.8011811 113.385827 0 1.78149606 141.865157 0.13779528
GW 205 61 0 1.78149606 141.865157 0 1.76181102 170.344488 0.13779528
GW 207 3 0 1.78149606 141.865157 0 0.79724409 141.865157 0.13779528
GW 208 3 0 -1.1712598 141.865157 0 -2.1555118 141.865157 0.13779528
GW 211 3 0 1.76181102 27.4261811 0 0.77755906 27.4261811 0.13779528
GW 212 3 0 -2.1751969 27.4261811 0 -1.1909449 27.4261811 0.13779528
GW 213 114 0 -1.1712598 141.865157 0 -1.1811024 84.6456693 0.13779528
GW 216 114 0 -1.1811024 84.6456693 0 -1.1909449 27.4261811 0.13779528
GW 217 114 0 0.79724409 141.865157 0 0.78740157 84.6456693 0.13779528
GW 218 114 0 0.78740157 84.6456693 0 0.77755906 27.4261811 0.13779528
GW 219 5 0 -1.1811024 84.6456693 0 0.78740157 84.6456693 0.195
GS 0 0 0.0254 ' All in in.
GE 0
EK
LD 5 0 0 0 2.49e7 0
EX 0 219 3 0 1 0
GN -1
FR 0 40 0 0 473 6
RP 0 1 10 1510 90 0 0 20 0 0

So I have no idea on net gains for this,

Here is a method to calculate Net Gain:

NetGain = RawGain+10*log(Feed-pointGain)
where Feed-point Gain = 4*Zr*Zo/((Zr+Zo)^2+Zi^2)

The [10*log(base10)]" converts to decibels, and Feed-point Gain is less than 1, since there is a loss.

Zo = characteristic Impedance for the transmission line connected to the antenna ( Zo=300 for the GH)
Zr = real part of antenna's complex impedance at a specific frequency
Zi = imaginary part of antenna's complex impedance at a specific frequency
RawGain = Gain output given by 4nec2 at the specific frequency

With a range of frequencies, youll need to plug the data into a spreadsheet.
After running 4nec2 for the range of frequencies, an option on the chart will be "Plot". This option was meant for another program so youll get an error message, ignore it. After the error message, a text file will pop up which you can copy and paste the data into a spreadsheet file. You can get Raw Gain, Real Impedance and Imaginary Impedance figures from the "Plot" option.

but I certainly have enough copper as some of you may recall.

Heh, youre going to need it. A couple of notes, avoid having the elements touch wood, use plastic (plexiglass etc) where the elements rest, and even keep that contact with the elements to a minimum. After you run that new model above for the full range of frequencies, youll note that for channels below 20, youll have less gain than your present antenna. Above that, much more gain.

[astupidoldman]

300ohm you kick arse with a monster Canadian boot. The shear beauty of modeling the GH is such a privilege to see. 30 minutes to run contraption 3. And then started running the other work you gentlemen have been doing. OMG! So I don’t know how much longer I can keep going on a couple hours of sleep a day, but I’ll catch up on sleep later. I have the Lotus symphony, but spread sheets aren’t my thing heh. I only use that and word for spell check. With what I am producing with the nec, I can clearly see that monkeying with the lengths of phasing line can really change up the harmonics. Just gorgeous. I am reminded of when I was a kid, sitting in a cold garage for hours at a time because it was the only exposed copper to ground I could attach my SW radio to. I’d really like to put that trailer hitch back on the jeep with a finely tuned array and drive around checking out and logging data. Mlord, M apparently for master builder. Beautiful work. Everybody’s models in nec are fantastic. As I diddle around, I’ll keep everyone posted. Thanks again.