Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement
About eHam.net

donate to eham
   Home   Help Search  
Pages: [1]   Go Down
  Print  
Author Topic: Privacy Fence Dipole??  (Read 9632 times)
KF4YNZ
Member

Posts: 11




Ignore
« on: December 08, 2007, 06:45:41 PM »

Hello all. I just moved into a small restricted community and wanted to know if anyone has had any success mounting a dipole about 6 feet off the goround along a wooden privacy fence? I want to mount a Hustler 6 band vertical, but am thinking a wire may appease the neighbors better. Thanks for you advice.
Logged
ONAIR
Member

Posts: 3687




Ignore
« Reply #1 on: December 08, 2007, 07:02:36 PM »

    I've made a variety of dipoles hidden in fences, behind walls and the like.  They work fairly well, althought not as well as dipoles strung up to normal heights.   Got any trees in the property?  Easy to hide verticals in them with buried radials.  Got an old used TV antenna or satellite dish laying around?  You can mount it on a mast on the roof or side of the house.  The mast or "cable" going to the TV antenna or dish can be your ham antena!
Logged
K5LXP
Member

Posts: 5902


WWW

Ignore
« Reply #2 on: December 09, 2007, 07:03:03 AM »

First you have to define "success".  One definition might be, to make infrequent contacts and being troublesome to tune, another might be to make contacts easily and enjoy trouble free operation.  You get one guess as to which definition of success you'll get with a 6ft high dipole.  That's not to say you won't ever make contacts or that it's impossible to tune.  But you're adding a built-in layer of difficulty.

That being said, if you have any option to put up a vertical, do it.  I'd be really suprised if your neighbors consulted you first before they buy that ugly set of patio furniture or planted a big tree that dumps leaves in your yard every fall.  A vertical is a very low profile unassuming structure, and a decent performer if installed correctly.  Put it where you can lay an adequate counterpoise, tune it up and you will have a setup you know has a decent pattern and efficiency.

Mark K5LXP
Albuquerque, NM
Logged
ONAIR
Member

Posts: 3687




Ignore
« Reply #3 on: December 09, 2007, 10:37:22 AM »

   Yep.  And don't forget flagpoles, or even artificial trees as vertical stealth antennas!
Logged
N3OX
Member

Posts: 8915


WWW

Ignore
« Reply #4 on: December 09, 2007, 11:08:40 AM »

If you do have trees, I'd encourage you to go with a vertical wire in a tree as well, or a flagpole or some such.  A 6 foot high dipole just won't do much for you.  You'll make some contacts but you'll have a lot of ground loss and you can do MUCH better with other types of antennas.

A magnetic loop (small transmitting loop) antenna hidden on your side of the fence would probably work better than the low dipole on most bands, probably even better if you could put a ground screen underneath it.

I built one and it really works.  Mine is about 4 feet in "diameter" and built from 3/4" copper tubing and uses a Jennings 10-200pF vacuum variable capacitor (15kV) for tuning, and will handle 100W.  

http://n3ox.net/projects/magloop/magloop1_lg.jpg

The disadvantage of these antennas is expense.  The capacitor will run you $150+ if you homebrew, and copper tubing isn't free either.  Then you need to hack together some remote tuning scheme.  I'm working on something simpler and cheaper but it's not there yet.

The advantage is that they can be tuned over a wide range of frequencies and are quite efficient for their size and extremely small; mine will tune from 5MHz to 21.35MHz with a calculated gain of maybe -8dBi down at 5MHz up to a couple dBi up at 21MHz ...

If I were stuck with a small antenna that I could hide behind a 6' privacy fence this would be the one.  It's a couple of S-units (maybe 10dBish) down from my big antennas (60 foot vertical on 40&30m , Moxon rectangle on 20m/17m ) but I can still work DX with it and have had some good ragchews with it on 40m...

- - - - - -

Whatever you choose the best thing you can do is to **try several antennas** and compare them against each other.

In a severe-compromise antenna situation there's often a big difference between different approaches.

73,
Dan







Logged

73,
Dan
http://www.n3ox.net

Monkey/silicon cyborg, beeping at rocks since 1995.
KE4BIW
Member

Posts: 42




Ignore
« Reply #5 on: December 15, 2007, 09:12:32 AM »

I use a 40 meter dipole running along the top of a six foot wooden fence and find it works just fine for my purposed. I easily work up and down the east coast and through the midwest from my NE Florida QTH.

I also use a Ventenna on a plumbing stack for 2M and 70 CM. Works great.

In addition, my 40 meter dipole serves as my "listening" antenna on all HF bands. When I hear some good activity, on 20 meters for instance, I quickly throw up a Buddipole on top of a 20 Ft. painters pole that stay attached to a wooden fence post with U-bolts. I don't play around with trying to get the best match, I just set the clips and antenna segments to the factory recommended specs, go back inside the shack and hit the auto-tune button. Works like a champ.

Logged
KB5IAV
Member

Posts: 42


WWW

Ignore
« Reply #6 on: December 18, 2007, 06:18:42 PM »

You said your fence is 6 feet high, but how long is it?  Perhaps instead of a dipole, you could experiment with a vertical loop instead.

To figure out the perimeter of a full wave loop, 1005/F(MHZ).  If you have a 30 foot long or so fence, combined with the height, you'll be able to build a 72 foot loop, which should be able to get you on 20 meters.  

If you feed the loop at the lower corner, you can rig up a switch or simply an alligator clip or the like at the upper corner opposite the feedline point you can run the  loop as either open or closed.  An open loop will resonate similar to a half wave dipole.    

The late Doug DeMaw, W1FB, described such an antenna in his W1FB's Antenna Notebook(p74-75) and reported good results using it on 80 closed, and 160 open, with the base only 6 feet off the ground.  He called the design a half wave open loop.

If you have a good tuner, feed it with ladder line or twinlead, and you should have multiband capability.  I'm currently experimenting with a 60 foot horizontal version of the half wave open loop, which I've fed with Radio Shack TV Twinlead into a MFJ 1:1/4:1 switchable  balun, which feeds into a LDG Z11 Pro Autotuner, and it loads on all bands 40-10 meters.

Of course, this will be a compromise antenna, but it will get you on the air!  Good luck.

     
Logged
K9MRD
Member

Posts: 381




Ignore
« Reply #7 on: December 23, 2007, 08:48:20 PM »

I have seen a vertical mounted on a rotor near the top of a 6' fence. When not in use the rotor put the antenna behind and parallel to the top of the fence and when operation was desired, a 90 degree rotation put the antenna vertical. You would need a radial field for this to work and it would not be hidden for daytime operation.

As Dan, N3OX suggested, a vertical wire antenna works very well. In fact, that is what I use on 80 meters and it is nearly invisible from the street. As with any vertical, you do need radials.

Good Luck & 73
Wayne

Logged
K3ANG
Member

Posts: 208




Ignore
« Reply #8 on: December 31, 2007, 08:28:28 PM »

One man's attempt at appeasing the HOA/CCR police.

http://tom.nc4tc.googlepages.com/helicalwindom

I don't know him, I never built it, YMMV, usual caveats.

73 & GS
de K3ANG
Logged
K3ANG
Member

Posts: 208




Ignore
« Reply #9 on: December 31, 2007, 08:35:21 PM »

Perhaps using your downspout and raingutter would be a better alternative.
http://www.qsl.net/wb3gck/spout.htm
Same caveats as above.
If you have vinyl spouts, you could run a wire *INSIDE* the spouts and then running the length of the gutter.
Just an idea.
More than my 2 cents.
de K3ANG
Logged
N5UBL
Member

Posts: 1




Ignore
« Reply #10 on: January 24, 2008, 12:30:58 PM »

Hustler Antenna Flagpole:
http://www.the6thfloor.com/news.php?item.253.9

I have seen more flagpole ideas using this antenna, than any other.  I bought this antenna when I lived in a house, now it sits unused in a storage unit.  **sigh** I have never built one of these but will someday.

TAK-Tenna: http://www.tak-tenna.com
I use one of these and it does the trick for regional contacts due to the height of installation.  It has a verty small footprint and doesn't look too bad, either.

Your mileage may vary.

73,
Stan
Logged
W4WSW
Member

Posts: 23


WWW

Ignore
« Reply #11 on: February 17, 2008, 05:50:10 PM »

Well Mr. Brown Welcome to the HOA Crap, I'm agree with one of the guys that say try everything and compare them, I did the same with my G5RV Jr. in the fence, (6-feet from groung) Work well in 40m may be not as I want but at least make very good contacts.........

For 10, 12, 15, 17, 20, 30m I'm using a screwdriver antenna and performs beter but not for 80 & 40m......

Now a friend of mine help me to build and install a Delta Loop (215 feet wire) that make me work even 160m, using an antenna tuner of course I can tune the wire all the way up from 160 to 10m......

Also I use an amplifier to help more a bit....

Good Luck & 73's.....
W4WSW  / Lou
Logged
Pages: [1]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!