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WB0LSR
05-03-2011, 04:42 PM
I've posted this elsewhere, but I'd like an many opinions and thoughts on this as possible. I'm in the middle of laying out a ground-mounted IMAX2000 install for 10-12m DX work. I live on a tiny city plot of land, fenced in. I have neighbors on all sides, and a homeowner's association that is hostile towards antennae.

I painted the antenna camouflage, and my plan is to mount it near ground level on one side of my property on the fence since there is a large tree there that will completely conceal the antenna. Since it's on the fence, if I use ground radials some of them will be in my neighbors yard, so that's out.

What do you guys think about the idea of grounding the antenna to the chain-link fence itself? It's not a ground plane exactly, and it's not resonant, but would it not suffice as some sort of counterpoise?

Any thoughts are welcome!

KG4CGC
05-03-2011, 04:50 PM
Absolutely! It is your best resource since it is already there. I would also experiment with the fence as a low band receiving antenna for casual listening. AMBCB and the Geritol Band, lulz.

NQ6U
05-03-2011, 05:10 PM
I have heard of people using chain link fences as ground planes. In fact, the guy who gave me my inductive 160m vertical antenna does just that and has recommended that I do the same. It's less than optimal but better than nothing.

One thing you might consider is using chicken wire or some other wire mesh as a ground instead of typical wire radials. You can often get by using a much smaller area that way, often as little and 8 feet square. Do a Google search and it should turn up something.

W5GA
05-03-2011, 05:32 PM
You only need 10' long radials for that ant. I'd use them rather than the chain link, it'll work better and won't be as prone to noise from the bad chain link joints. They also don't necessarily have to be equidistant around the antenna for it to work. The last 4-BTV I used had 36 radials in a butterfly pattern, and it worked very well.

W3WN
05-03-2011, 06:28 PM
Well, my HF6V is mounted on my chain-link fence. It was originally on the back section, roughly centered. I had to move it to the side fence near the back after some storm damage 2 winters ago.

Works like a champ. Key was to make sure the feed point is above the top of the fence, of course.

I've also added a few radial wires into the yard and (with his permission) along the back of my next door neighbor's yard as well.

Now, I don't have an HOA to deal with, so I can't address how they would react to it.

And not wanting to sound like a broken record, but can you put up a flagpole in your front lawn? You can find some fiberglass ones around 24 feet tall online for about $75 including mounts... run a wire inside the fiberglass and no one will ever know...

n2ize
05-03-2011, 07:53 PM
There was a guy in Manhattan who worked some great DX on 10-20 with an antenna on his fire escape using the fire escape itself as a "ground plane". And he didn't do too bad on 40 and 75 with some wire hanging out his window that he snagged in some trees.

KC2UGV
05-04-2011, 08:19 AM
I'd say the chain link would work fine for a counterpoise, but as Doug said, radials for that antenna are small, and cheap. Using specific radials for it removes one less variable from possible issues you may face.

WB0LSR
05-04-2011, 10:59 AM
Thanks a lot guys! I appreciate the input so far.. I had thought that it was worth a shot, so I'll try it and see what happens. Worst-case scenario is that I need to find a way to keep all the radials on my property if I end up needing them.

W5GA
05-04-2011, 12:16 PM
Worst-case scenario is that I need to find a way to keep all the radials on my property if I end up needing them.
Nothing says that they have to be in a straight line, you can run them however they'll fit.

WB0LSR
05-04-2011, 01:16 PM
Very good to know.. I was sort of under the impression that not having the radials spread equidistantly around the antenna would negatively affect the radiation pattern to a large degree.

KC2UGV
05-04-2011, 01:17 PM
Very good to know.. I was sort of under the impression that not having the radials spread equidistantly around the antenna would negatively affect the radiation pattern to a large degree.

If it's in the center of the yard, they would be more or less spread equidistantly :)

KG4CGC
05-04-2011, 01:19 PM
Of course the smart assed option would be to bring in a lot of Carolina red clay which is like an antenna mirror due to its high iron content.
;)

NQ6U
05-04-2011, 01:22 PM
Of course the smart assed option would be to bring in a lot of Carolina red clay which is like an antenna mirror due to its high iron content.
;)

Or southern California clay. Different metal (aluminum) but same result.

WB0LSR
05-04-2011, 01:31 PM
Actually, if you go just outside of the STL metro area in any direction you run into red iron-rich clay everywhere you go.. MO is full of iron.

WØTKX
05-04-2011, 01:31 PM
As far as radials are concerned... something to consider is ground screen.

http://www.sherweng.com/documents/GroundScreen-sm.pdf

Here's a wild stealth antennas system. Very impressive.

http://www.ac0c.com/main/page_antennas__homebrew_gen_4__antenna_array.html

W2NAP
05-04-2011, 01:57 PM
another idea. might sound a bit wierd. if the tree is on his property and he can climb. imax at the top of the tree. (alot of cb'ers around here would slap the antron or imax up at the top of a 60ft tree and do pretty well)

WB0LSR
05-04-2011, 01:59 PM
another idea. might sound a bit wierd. if the tree is on his property and he can climb. imax at the top of the tree. (alot of cb'ers around here would slap the antron or imax up at the top of a 60ft tree and do pretty well)

That thought had crossed my mind too.. but then I would be relying more on my camo paint job than I'd like. The imax sticking out from the top of the tree will be pretty conspicuous.

W5GA
05-04-2011, 03:57 PM
Very good to know.. I was sort of under the impression that not having the radials spread equidistantly around the antenna would negatively affect the radiation pattern to a large degree.
With my 4-BTV, I'm sure it did...but not to enough of a degree that I ever noticed. I ran them in a bow tie because the antenna was only about 15-20' from the house. Another 15-20' on the other side was horse pasture, and I didn't want them tangled in the wire. So, that took care of having any radials running N-S. I put 36 random length radials, all running roughly E-W. They weren't really "random", all were at least 35' long (for 40M), I just didn't bother to measure them. With a ground mount, there is no need to have different radials for different bands. This is NOT true of an elevated vertical. If elevated, you need to have at least a pair of radials per band. You tune them the same way you do a dipole. For a ground mount, what matters is that they be there. Just make them all long enough for the lowest freq. and they'll work great on all bands above that. If you have to bend the radials, zigzig them, horse shoe them etc doesn't seem to matter. It may effect the feed point impedance a bit, but it'll still play - and play well (for a vertical). Don't try to compare its performance to a beam, because it'll really seem sucky by that measure. A good installation will equal or better a 1/2 wave dipole at most elevation angles. Where it really shines is on DX, due to a low radiation angle. For local work, you're better served by a LOW (less than 1/4 wave high) dipole.

WB0LSR
05-04-2011, 04:14 PM
^I see.. that makes sense. I don't need a perfect pattern anyway, so I think there is a very good chance I'll be able to make this work!


If it's in the center of the yard, they would be more or less spread equidistantly :)

I also considered that, but that removes my concealment. This install has to be very stealthy, otherwise my anal-retentive neighbor to the north will whine and bitch no end and take her case to the HOA. She keeps her nose up everybody's asses around here, much to the dismay of the entire neighborhood. At any rate, concealment is the best option for my sanity.

W2NAP
05-04-2011, 07:34 PM
That thought had crossed my mind too.. but then I would be relying more on my camo paint job than I'd like. The imax sticking out from the top of the tree will be pretty conspicuous.

just paint it od green lol.

it would be a "wont notice it unless your really looking for it" kinda deal if the tree is tall enough

W7XF
05-12-2011, 01:47 PM
I know some of the HOA Nazi's in Tucson actually use field-strength meters to detect stealth installations...one notable HOA near my UNRESTRICTED QTH actually spells out the only LEGAL transmitters: Baby monitors, cordless phones, cell phones, bluetooth, 802.11x devices, to name some..as well as the usual spurious devices. And, they put aluminum sheeting on the roofs (under the shingles) to prevent attics being used for stealth antennae. Wonder if they actually discourage licenced hams from purchasing a home in those subdivisions???

W3WN
05-12-2011, 02:00 PM
^I see.. that makes sense. I don't need a perfect pattern anyway, so I think there is a very good chance I'll be able to make this work!< snip >You hardly ever get a perfect pattern anyway. How many of us can install a vertical in the clear, with no obstructions whatsoever (buildings, trees, fences, hills, indian burial mounds, etc.) within a few hundred yards?

A 1/4 wave vertical needs an electrical counterpoise to work correctly. In theory, the counterpoise or radials should also be an electrical 1/4 wave for each band desired, should be equally spaced, should be straight, etc.

That said, the reality is that for most installations, just get down as many radials as you can, in as many directions as you can, as long as you can. You won't be ideal, but you'll radiate a signal.
< snip >
I also considered that, but that removes my concealment. This install has to be very stealthy, otherwise my anal-retentive neighbor to the north will whine and bitch no end and take her case to the HOA. She keeps her nose up everybody's asses around here, much to the dismay of the entire neighborhood. At any rate, concealment is the best option for my sanity.When we moved into our current home, I did the same thing I did when moving into the previous two homes I'd bought.

At least one vertical went up in the back yard right away. No radials, no coax, no tuning, no nothing. Didn't get to hooking it up for close to 6 weeks, with everything that we needed to do.

My then-next door neighbors asked what it was. I told them. They said "that's pretty neat!" (so help me, yes they did) and we talked about it for awhile. They also asked about interference, and we talked about that too.

6 weeks or so later, when I go to string coax and then started to operate, nobody batted an eye. After all, I hadn't caused any interference for weeks, so clearly I wouldn't do so now.

I have yet to have an interference complaint. None. Nada.

Of course, YMMV, VWPBL(STn)

KG4CGC
05-12-2011, 02:01 PM
I know some of the HOA Nazi's in Tucson actually use field-strength meters to detect stealth installations...one notable HOA near my UNRESTRICTED QTH actually spells out the only LEGAL transmitters: Baby monitors, cordless phones, cell phones, bluetooth, 802.11x devices, to name some..as well as the usual spurious devices. And, they put aluminum sheeting on the roofs (under the shingles) to prevent attics being used for stealth antennae. Wonder if they actually discourage licenced hams from purchasing a home in those subdivisions???
IT'S FOR THE CHURLDINS FER CRISSAKE! :lol:

WB0LSR
05-12-2011, 08:22 PM
Thanks for the advice!


VWPBL(STn)

'splain please?

W3WN
05-12-2011, 08:40 PM
Thanks for the advice!

VWPBL(STn)
'splain please?I'm glad you asked.

Did you ever watch the old Talk Soup program on "E!" This was one of John "Skunk Boy" Henson's favorite lines:

Void Where Prohibited By Law (Sorry Tennessee!)

WB0LSR
05-13-2011, 09:18 AM
LOL.. I see.

N8YX
05-15-2011, 07:43 AM
Get yourself a 6BTV, about 25ft of PVC pipe into which the 'BTV can slide and a toilet-tank float. Paint said float gold, install on top of PVC and put the assembled antenna into your new "flagpole". For mounting I would use a 4-6ft pipe driven into the ground. Lay 30-40 25' radials in the grass using a slitter and sod staples. At the base of the flagpole, install an SGC-230, AH-4 or similar random-wire tuner. The make and model of rig you're using will determine which tuner to purchase, as some transceivers can directly control an attached remote tuner.

Place a nice concourse of flagstones around the base (to hide the tuner) and install some low-voltage directional 'flag lighting' (which gives you sufficient cover to run the coax, tuner control lines, etc).

Ceremonially raise and lower the flag in inclement weather, as you are supposed to do. Extra points awarded for doing this every morning/night. If anyone bitches about it, get in touch with area veterans groups then explain your plight to them. :yes:

N8YX
05-15-2011, 07:46 AM
I know some of the HOA Nazi's in Tucson actually use field-strength meters to detect stealth installations...
Any radio enthusiast who willingly resides in such environs is a fucking moron.

I'd far rather take my chances out amongst the unwashed country masses than with a group of anal-retentive, restrictive, cloistered little giddy-biddies such as can be found in those "upscale" developments. :roll:

KC2UGV
05-15-2011, 07:56 AM
I know some of the HOA Nazi's in Tucson actually use field-strength meters to detect stealth installations...one notable HOA near my UNRESTRICTED QTH actually spells out the only LEGAL transmitters: Baby monitors, cordless phones, cell phones, bluetooth, 802.11x devices, to name some..as well as the usual spurious devices. And, they put aluminum sheeting on the roofs (under the shingles) to prevent attics being used for stealth antennae. Wonder if they actually discourage licenced hams from purchasing a home in those subdivisions???

Good thing they state "Legal Transmitters". Like amateur gear :)

As an aside, I wonder what would happen if one were to load up the aluminum sheeting?

KG4CGC
05-15-2011, 12:10 PM
Good thing they state "Legal Transmitters". Like amateur gear :)

As an aside, I wonder what would happen if one were to load up the aluminum sheeting?
Yep. I bet it's broadbanded too.

W3WN
05-16-2011, 07:32 AM
Good thing they state "Legal Transmitters". Like amateur gear :)

As an aside, I wonder what would happen if one were to load up the aluminum sheeting?
Well, it's one way to get on the air with a bang...

W5GA
05-16-2011, 08:47 AM
Good thing they state "Legal Transmitters". Like amateur gear :)

As an aside, I wonder what would happen if one were to load up the aluminum sheeting?
I had dedicated 40m vertical on a roof covered with ~2500 sq. ft. of metal (steel) roofing once. Worked great! You just have to make sure that all the sheets of roofing are really well tied together electrically.

W1GUH
05-22-2011, 07:05 PM
There's a ham in NYC who runs a 33' invisible (No. 26 wire) random wire to a tree across the street and loads that up against ground. He really gets out well...in fact...well enough to be an NCS for ECARS.

And that HOA that regulates RF emission? Somehow I can't fathom how a private entity like that has any jurisdiction whatsoever in a case like this. But...lawyers are lawyers and there's probably some weasel-wording in the covenant that gets around that issue.

W5GA
05-23-2011, 08:26 AM
And that HOA that regulates RF emission? Somehow I can't fathom how a private entity like that has any jurisdiction whatsoever in a case like this. But...lawyers are lawyers and there's probably some weasel-wording in the covenant that gets around that issue.
If someone was inclined to fight it, I think the Communications Act of 1934 would override any covenant regarding emissions.

W1GUH
05-25-2011, 08:18 AM
If someone was inclined to fight it, I think the Communications Act of 1934 would override any covenant regarding emissions.

Might be restrictions that stipulate the the emissions can only happen nocturnally!

KG4CGC
05-25-2011, 01:02 PM
Put up a small vertical on a mast that clearly has no coax attached to it. When the complaints come in, nail them to the walls as blatant liars and trouble makers. As trouble makers, they could be rode out on a rail like certain furry species of rodents.

W3WN
05-27-2011, 08:07 AM
Under the theory of putting one's money where one's mouth is...

Just ordered a 22 foot fiberglass flagpole (with flag and ground mount) from a company called Balkowitsh Enterprises in Bismark ND. Cost was $89.95 including shipping. I should be seeing it in about a week or so.

You see, I've started the process of rehabbing the front porch. Put a layer of concrete sealer on it the other day, and it has filled in the cracks that were causing leaks into the garage/storage area underneath. This weekend, a coat or two of outdoor concrete paint goes on top of THAT as a further sealant. Then I start building the deck right over it it.

And when the deck is done, some new landscaping will go in front. Including a flag pole.

...of course, as the deck goes in, there will be radials run right through the support beams over to the pole location (a lot easier to do BEFORE the deck planks go in place... no, I won't be able to get to them from underneath, the deck is going RIGHT on top of the concrete, raising it up the width of a 2x4), and there will be a hidden electrical outlet & sealed plastic container right next to it (for the auto tuner)...