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I have been following this Forum for years. I think that I have read almost every thread on the Gray-Hoverman antenna (many, many hours!). It was here that I read about the NEC modeling software. I thought that I would have to work for the government before I could have access to software like this! My first DIY antenna was a Channel 13 Yagi. It actually worked! The snow was gone (old analog days), perfect picture! I should have done this years ago. The second antenna was a Channel 5 qubic-quad. It also worked. Time for the UHF.

I set out to build the best UHF antenna possible, sparing no effort or expense. After many hours of searching, I looked at “astupidoldman’s” hov-10-new. Not so stupid. It seems that thru pure tenacity (and probably a good computer) he has produced a remarkable design, all with #6 wire. It looked like the “ultimate” antenna design I was looking for. After downloading, centering, converting to inches and rounding to the nearest sixteenth, I ran NEC. Too may segments! After reducing the segments it produced similar results. Good, it passed the convergence test. It also passed the AGT test. Time to build.

You can see some photos on Photobucket in Hermitman’s file. I call it “Wings". This thing is big, 8’-8” tall, by 7’-5” wide. I know that many of you will ask: What is the frame made from? It is fiberglass C-channel that is found on ladder side rails. This is scrap C-channel from a local manufacture. Many of the locals use it to make farm gates ect. These antennas were built for my cabin located in a valley in the Southwest Virginia mountains (Smyth Co.). “Wings” had to have a heavy duty rotor, a DIY. To look at the ridge tops it had to have a tilter, again DIY. I had to build a jib with a winch just to lift it on the pole. Design and construction has taken well over a year!

Although the gain was excellent, the design had a nagging problem, poor SWR on some channels. How to correct? Stubs are the usual answer, but they work well only at one frequency. I needed stubs for many frequencies. Only answer, I needed adjustable stubs. The adjustable stubs are made form an old set of rabbit ears (cut down) with a model airplane type servo to remotely adjust them. Calculations of stub corrected Net Gain range from 14.4 to 18.3db. To complete the system, it has a Tin Lee MT-37X balum and a Research Communications 9261 preamp.

How does it work? I can get all the local channels in VA, TN, and WVA. I consistently get WXII in Winston-Salem, NC and WCNC in Charlotte, NC. When tropospheric ducting is working, I can get WATE in Knoxville, TN and four stations in Highpoint, NC. I could not have gotten this far without your fourm. I still spend many hours on it. Keep up the good work!
 

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You can see some photos on Photobucket in Hermitman’s file.
Can you post a link ? All I see is an alien bug creature of some sort when I search, heh.

The adjustable stubs are made form an old set of rabbit ears (cut down) with a model airplane type servo to remotely adjust them.
Thats a pretty good idea. Model racing boats also use similar servos.
 

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Thanks nikiml.

Thats quite some setup. :p

What is the frame made from? It is fiberglass C-channel that is found on ladder side rails. This is scrap C-channel from a local manufacture.
How's it holding up in the wind ? I would think it would catch a lot of it.
 

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I searched, but couldnt find it either. It was some time ago, and I do recall it. :(

I think its just JEDs GH10s, 2 vertically stacked and 2 horizontally stacked in a cross shaped configuration.
 

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Astupidoldman's post was an old one. (I have been at this for a long time.) It is in Autofils thread: GH "Gold Standard" for UHF (plans, notes by j3d).

Here is it's address: http://www.digitalhome.ca/forum/showthread.php?t=96483 (Post #16)

Wings recently survived a wind test. We had a cold front move thru and had some strong straight line winds. Trees down, power out and even a truck was blown over. This is kind of wind is rare for Southwest Virginia.
I happened to be at the cabin that day. I was watching the trees to see which one was going to fall so I could plan my escape!

The DIY rotor is strong. The post is a 6x6 inch, three feet in the ground and anchored to the cabin. The mast is a 1 inch galvanized pipe. The rotor is made from a milling machine spindle in which the 1 inch pipe will just fit into the tool end. Unless a tree fall on it, it should stay up there.

Those of you who have a good computer and know how to use NEC, please run the design. It could be that Hermitman and Astupidoldman are both stupid.
 
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