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W3WN
06-24-2013, 11:58 AM
As some of you may recall from earlier threads over the last couple of years (like this one (https://forums.hamisland.net/showthread.php/17689-A-Question-for-the-Antenna-Gurus?highlight=Flag+Pole+Vertical)) I've been playing around with the design for some form of a home brewed flag pole vertical for awhile.

Well, it finally got a field test -- on Field Day, of course.

W3WH asked me to bring it out to the N3SH FD operation. Since we were trying some other things, why not bring this out too as a demo of what you can do? So, I did.

I have a better picture of it at home; this one is clipped from another photo of Sean N3NWR's...
9830
The antenna itself is 4 sections of Army surplus aluminum masts. The base section is a 2 foot section of the fiberglass masts that match the aluminum ones (the top half of one), and it's being held in a jury-rigged Glen Martin 3 foot rooftop tower mount. Radials were attached right below the feed point, just above where the fiberglass mast is being clamped up top.

The four sections are held together with sheet metal screws, primarily for mechanical stability.

The top, which is clipped out of the photo, holds an eye bolt that the flag rope runs through. The one I have in place is actually too long, so it's going to get replaced with a smaller one or a pulley for the final installation. In lieu of a ball or symbol (plastic Eagle) on top, there's a short piece of wooden dowel, which has... don't laugh... an oval wooden replacement chair foot on it. I need to find something a little better!

Because the antenna is pretty much non-resonnant, an SGC tuner was placed at it's base (not yet installed when the picture was taken). And about a dozen radials of misc. lengths were attached.

How did it work? Very well. Multiple contacts on 10, 15, and 20 across the Northeast and Midwest.

Total cost? The aluminum & fiberglass masts, including 3 other sections of aluminum that I didn't use in this configuation, were $30. The other misc. hardware, another $10 or so. (I'm not counting the GME mini roof tower, since that won't be used in the final installation). Add in another $10 for the rope & flag hooks, and (because W3WH forgot to bring his) $10 to Wallyworld Saturday morning for a US flag.

Next step? I have to "fix" a few minor things -- eyebolt and decorative top piece. Then dig a hole in the front yard. I had had the fiberglass already cemented in, after building the new deck on the front of the house, only to have the boss decide she didn't like the location (that's why the fiberglass got cut!!), so the 'new' location is only a few feet away -- where I have a temporary, portable fiberglass flag pole right now. There's already a coax feed in place. So sometime this summer, the temporary pole comes down, the permanent one goes up. And the radials go out across the lawn, most of them will be hidden by mulch (flower garden in front of the house) or slipped under the grass.

I hope to have the antenna up & running by the fall. Famous last words.

I am going to take one last look at going to 20 feet, but considering that we have a ranch house, that may be too tall, aesthetically speaking. I don't want this to be a distraction, but to blend in. What better way to demonstrate how a stealth antenna should work, right?

WX7P
06-24-2013, 12:12 PM
Nice.

I'm going to forward this to my buddy in CA who lives in a no-antenna zone.

PA5COR
06-24-2013, 12:35 PM
I find my 77 feet tall Inverted L aesthetically fitting very nice to the 30 feet tall house to be honest....;)
You could paint it to camo it to the colour of the house, i didn't even try to hide the 3 1/2 inch pipe of the inverted L nice and shiny ;)

W3WN
06-24-2013, 12:46 PM
I find my 77 feet tall Inverted L aesthetically fitting very nice to the 30 feet tall house to be honest....;)
You could paint it to camo it to the colour of the house, i didn't even try to hide the 3 1/2 inch pipe of the inverted L nice and shiny ;)Well, I wouldn't either. But is your L in the FRONT of the house?

Keep in mind that one of the key ideas here is to keep it a "stealth" antenna, which means it has to blend in. A 24 foot, let alone a 77 foot, pole in front of a single story ranch just doesn't "look" right, and why draw attention if you don't have to?

Also, I've taken a good look at other flagpoles in the area. Most are unpainted aluminum, or painted silver. Many, however, are painted white, black, or grey. So leaving the poles "as is" in camo green isn't that out of place. I will have to go to a hobby store and find a little camo-green "touch up" model paint to use on the sheet metal screws... that will help them blend in, and will also provide a small amount of weather protection from rust. Not much, just a little.

PA5COR
06-24-2013, 12:53 PM
Nope, but it would not matter if it is in the front or back in my case ;)
Click piccie to enlarge, you will "almost" see my Fritzel FD -4 running from under the beams to the other blocks of housing.
In stealth mode i used the camo glass fiber sticks of 4 feet long that can be coulpled together and have a thick copper wire running in it.
Flagpoles work, standard lengths here are 20 to 25 feet long, nobody cares if you put one up here, no permission needed too.
From the top of the L a 77 feet long wire runs ito the row of trees behind it to 45 feet high.
3000 feet of radials does the rest with the MFJ 998 legal limit tuner just behind the wall inside the house tuning it from 160 -10.

http://www.zendamateur.com/download/file.php?id=4654&t=1 (http://www.zendamateur.com/download/file.php?id=4654&mode=view)

W3WN
06-25-2013, 08:02 AM
Here's a better picture of the FPV from last Saturday:
9833

W3WN
10-30-2014, 01:40 PM
Just in time for Halloween, time to resurrect a zombie thread... :evil:

The boss was initially reluctant about my putting a 20 foot flag pole in front of the house. But for about a year, year-and-a-half, I had a fiberglass temporary one in place. She came to like it, as I knew she would.

So, a few weeks back, I finally got the FPV re-assembled and swapped it in place of the temporary flag pole.

Oh, sure, that sounds simple, right?

First problem was, the insulator that I used to separate the base from the active part of the antenna failed. Whole thing came down one windy night, fortunately, no damage. Spent a few bucks with Max Gain Systems, got a 2 foot solid 1 1/2" thick fiberglass rod -- $17 plus shipping, but well worth it.

Second problem was, the FPV began to rotate in the wind. That was all my fault, I didn't mix the Quickrete correctly, and it didn't "take". So a couple of evenings ago, I took the FPV out of the ground, broke up the concrete, and redid the whole thing. It's holding now.

Next step is to get some radials in place & connect the feed point. I'll start on that this weekend.

Pictures will be forthcoming.

kd6nig
10-30-2014, 02:20 PM
One handy thing you could do that would explain all the wiring is to put a light at the base of it.

Wouldn't want old glory to be flying unlit, would we? :)

KG4NEL
10-30-2014, 03:13 PM
Mo radials mo betta.

KA9MOT
10-30-2014, 05:34 PM
Good job Ron! I did something similar when I went portable for the Illinois QSO Party, except I just used mine to support a dipole in an inverted V configuration.

1330213303

W3WN
10-31-2014, 07:41 AM
One handy thing you could do that would explain all the wiring is to put a light at the base of it.

Wouldn't want old glory to be flying unlit, would we? :)That's coming.

My secret plan is that the box holding the light fixture will actually hide the remote tuner.

KA9MOT
10-31-2014, 09:43 PM
A very good plan!