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eHam Forums => Antenna Restrictions => Topic started by: KF7ZFC on March 25, 2019, 02:10:33 PM



Title: Radials and counterpoise for very small yard area
Post by: KF7ZFC on March 25, 2019, 02:10:33 PM
I live in an HOA community. My daughter bought a house that has a separate 2 bedroom apartment for my wife and I. With that we have a decent size side yard. Of that I have 20 feet by 14.5 feet for my antenna system. Originally I was going to go with the MFJ mag loops but the initial cost and some of the negative reviews ended that. I have gone with 4 hamsticks for 40, 20, 17 and 10.

The problem is that I really don't have room for 1/4 wave radials or even 0.15 wave radials as N6LF talks about.

What if I covered this 20 x 14.5 area completely with aluminum roof flashing or perhaps chicken fence wire (to lower cost),

Would this give me something that would work acceptably rather than trying to put down 16 sets of radials that will be on top of each other?

My wife will not let me use elevated radials she still wants the yard to look like a yard. The flashing and chicken fencing would be hidden under the small stones that make up many yards here in Arizona desert


Title: RE: Radials and counterpoise for very small yard area
Post by: K5LXP on March 25, 2019, 04:11:52 PM
You wouldn't put down 16 sets of radials, because ground radials become untuned.  You would just put down as many as you can, as long as you can.

That's a pretty small spot as far as HF is concerned.  You can't extend those bounds with the idea radials would be buried/concealed?

A hamstick is a pretty poor performer on 40.  You can't go any longer than this?  Maybe a 5BTV?

Mark K5LXP
Albuquerque, NM
 


Title: RE: Radials and counterpoise for very small yard area
Post by: AC2RY on March 25, 2019, 04:13:20 PM
I live in an HOA community. My daughter bought a house that has a separate 2 bedroom apartment for my wife and I. With that we have a decent size side yard. Of that I have 20 feet by 14.5 feet for my antenna system. Originally I was going to go with the MFJ mag loops but the initial cost and some of the negative reviews ended that. I have gone with 4 hamsticks for 40, 20, 17 and 10.

The problem is that I really don't have room for 1/4 wave radials or even 0.15 wave radials as N6LF talks about.

What if I covered this 20 x 14.5 area completely with aluminum roof flashing or perhaps chicken fence wire (to lower cost),

Would this give me something that would work acceptably rather than trying to put down 16 sets of radials that will be on top of each other?

My wife will not let me use elevated radials she still wants the yard to look like a yard. The flashing and chicken fencing would be hidden under the small stones that make up many yards here in Arizona desert

Is the whole yard bigger than 20x14 ? You can use remaining area - just hid radials under ground. They are not required to be straight wires also and can follow walkway, fence etc. If you provide google map location with satellite view, people here may give you some ideas.


Title: RE: Radials and counterpoise for very small yard area
Post by: KF7ZFC on March 25, 2019, 06:44:50 PM
HOA would not like a tall vertical.

The visible part of my hamsticks  appears to be a plant trellis


Title: RE: Radials and counterpoise for very small yard area
Post by: W1BR on March 26, 2019, 06:32:44 AM
You do not need a solid conductive surface.  Your plan to use chicken wire has a lot of merit.  Check out this web page:

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

Personally, I would opt for a different radiator system, if possible.  How much vertical wire can you run?  There are remote antenna tuners that can handle the matching--not the cheapest solution, I know.

Pete


Title: RE: Radials and counterpoise for very small yard area
Post by: W1VT on March 26, 2019, 07:07:05 AM
The digital mode FT8 or CW can allow many  hams to make contacts with an inefficient antenna, even though voice contacts are too frustrating to be fun.
The second day of a phone contest like the CQ WPX contest is also a good time for a highly compromised station to make a few voice contacts.

https://www.cqwpx.com/
CQ WPX Contest Dates
SSB: March 30 - 31, 2019


Title: RE: Radials and counterpoise for very small yard area
Post by: KF7ZFC on March 26, 2019, 08:25:08 AM
Pete

Finances limit my choices at the moment. This is a new HOA and there are only 2 trees  my yard and they are about 7-8 feet tall

Thanks for the link

Steve


Title: RE: Radials and counterpoise for very small yard area
Post by: K5LXP on March 26, 2019, 04:55:23 PM
 
You're welcome to try it.  But I wouldn't go through any extraordinary effort to install it because frankly, at best it's going to suck.  Better than nothing for sure, but not by much. 

Guessing there's a house associated with this yard that the hamshack is in.  I'd be working the angle of putting an antenna somewhere on the house if the yard idea is a bust.  An elevated doublet or loop would be far more effective and efficient than a ground mounted hamstick over a compromise radial field.

I've lived under far greater restrictions than this, and that's what I've done.

Mark K5LXP
Albuquerque, NM
 


Title: RE: Radials and counterpoise for very small yard area
Post by: KF7ZFC on March 26, 2019, 06:18:53 PM
Mark

An elevated doublet would not be allowed. The HOA is very aggressive in making sure the covenants are kept. A non-ham put up a flagpole with an American flag that was higher than the rules and he was forced to reduce the height.

If the counterpoise/ground screen only gives me marginal operation, then I will need to put aside money and get an MFJ loop or build my own loop.


Title: RE: Radials and counterpoise for very small yard area
Post by: KL7CW on March 26, 2019, 07:23:52 PM
There are 4 things which are working against your hamstick idea.  First is the compromise radial situation.  Second is the hamsticks are too short for any reasonable efficiency, especially the 40 meter one. The third factor is in most typical situations like yours, you are surrounded by structures such as brick fences, stucco over wire house walls, and other obstacles. The fourth is your limited finances.  I have operated when I visit friends and relatives in the SW desert areas and it is possible.  Usually I do not operate from their home, but walk to a park, toss a wire into a tree and have a good time with my little QRP CW rig, usually on 20 or 40 meters.  However I have had some success at their homes and other areas.  I know your finances are tight, but if you could buy a remote antenna tuner (cost probably a few hundred dollars) you could load even rather short wires and have performance much better than the even shorter ham sticks.  Just one example a SGC 237 will load something as short as 7 feet on 3.5 MHz or above.  Now for sure this would not work too good on 3.5 or 7 mHz, but something like a 20 or 25 foot wire would probably work (OK) on 40, 30, and 20 meters.  If no room for the wire, I have looped something like a 17 foot wire over probably a 10 foot high tree.  Go up 10 feet, then over the top of the tree perhaps 2 feet, then drop down the opposite side of the tree to perhaps 5 feet above ground.  The remote tuner would be right at the bottom of the vertical wire.  Hook up the best counterpoise you can to the tuner ground.  Use small insulated wire...something like 24 ga (perhaps green, brown or gray ?).  This antenna will still "suck" but I have had some success with similar antennas on 40, 30, and 20 meters.  Have not tried this idea on a 7 foot tree, but if you could obtain something like a 10 or 12 foot tree (and it will grow taller).  A U shaped antenna may work nearly as good as a vertical, especially if you do not bring the far end of the antenna down too far toward the ground.  Before purchasing a tuner, you could just drape something like a 17 foot wire over your 7 foot tree and feed it with coax and hook up the counterpoise to the shield, then trim the length for resonance on 20 meters.  This would at least give you an idea if the concept is worth improving upon.  The ARRL and RSGB and I think VK3YE and others have books on stealth antennas.  I have even had some success loading up umbrella tables, rain gutters, and other miscellaneous objects, but usually need a tuner.   Good Luck   Rick  KL7CW


Title: RE: Radials and counterpoise for very small yard area
Post by: KF7ZFC on March 26, 2019, 08:03:49 PM
Thanks Rick


Title: RE: Radials and counterpoise for very small yard area
Post by: K5LXP on March 26, 2019, 08:59:55 PM
An elevated doublet would not be allowed.

Invisible ones are.

Quote
I will need to put aside money and get an MFJ loop or build my own loop.

The efficiency of a loop is nothing to write home about either, plus are finicky to tune. 

It doesn't sound like you have a lot of experience on HF.  Not a criticism, just an observation.  Your post is like many before on the forums seeking the most expedient solution to reduced space or restricted operations.  I'm here to say that compounding compromise solutions on top of each other is a formula for failure.  You'll put a bit of effort into making it stealth/aesthetically palatable, discover that it's a PITA to get/keep tuned, you'll become disenchanted with the result, then lacking any direct advice or turnkey solution will throw in the towel proclaiming HF is impossible from your location.

But if you view it from the perspective from others like myself that have been there and done that, while not ideal there is no doubt in my mind there is a more efficient and effective antenna solution than a hamstick in the yard.  It will take the form of some kind of wire antenna, strung in a way and place that will escape the scrutiny of the HOA.  This could be under the eaves, along the roof ridge, or strung in a stealth way between structures or trees.  There can be feed challenges to random wires but you work with what you have and there is always a way.  I have put HF antennas everywhere I've lived including apartments, military barracks and a house on the national historic register.  It can be done.

Another solution is much more straightforward.  Deploy temporary full size antennas right in the middle of the yard when you want to operate, and take it down when you're done.  An extension of this idea is something like a multiband vertical on a tilt base you set up to operate, and lay down to store. 

You're welcome to go down the snake oil antenna path and see if that works for you.  But just be aware there are better and easier options that are very budget friendly.

Mark K5LXP
Albuquerque, NM
 


Title: RE: Radials and counterpoise for very small yard area
Post by: KF7ZFC on March 27, 2019, 09:27:28 AM
Mark

My location on the side of the house is forward near the street. Stringing a small diameter wire between my 2 Olliander trees is visible. I used 18 gauge copper wire I have on hand

The home is typical AZ stucco construction. I can run a 10 foot wire vertically up the wall and then 7 feet under the eaves. Would this be better than the hamsticks in spite of the chicken wire grid used with the stucco construction?

Steve
KF7ZFC


Title: RE: Radials and counterpoise for very small yard area
Post by: VE3PP on March 27, 2019, 09:37:40 AM
How about the old stand by, the Hustler 4BTV inside white PVC pipe with a flag mounted to the pipe?

Lay down as many radials are you can in the space you have, they don't have to be straight line radials.

Surely the HOA would not make you take down your "Flagpole" ?

http://www.hamuniverse.com/kx9dk4btvflagpole.html

https://flagpoleantenna.com/collections/dx-flagpole-antenna

https://zerofive-antennas.com/product-category/flagpole-antennas

https://www.youtube.com/watch?v=Grc2aaY32ZA

http://static.dxengineering.com/pdf/flagpole_antenna.pdf



Title: RE: Radials and counterpoise for very small yard area
Post by: WW7KE on March 27, 2019, 09:43:25 AM
My house is of the same construction.  I found that I have to keep my antenna or any portable radio at least 10 feet away from the house in order to prevent reception of all those noise-making devices inside.  This is despite the chicken-wire being a 20-40 db attenuator, depending on frequency.  The noise still gets through if the antenna is too close to the house.

Indoor antennas absolutely will not work with this kind of construction.  Don't even think about them.  And that includes any form of antenna, from AM broadcast to the ham bands to UHF-TV.


Title: RE: Radials and counterpoise for very small yard area
Post by: KL7CW on March 27, 2019, 10:15:08 AM
WW7KE makes a valid point that often reception is your biggest problem in typical urban settings.  Before spending effort and money on a transmit antenna, I would suggest that you string up a temporary wire and see if you can receive anything besides noise from all the plasma TV's, Wall warts, various lighting schemes in your house and other near (50 feet ??) houses.  Every situation is different.  For transmitting running the first 10 feet vertically directly on the wall, or probably even inches away I would guess for sure would attenuate much or most of your power.  I have never tried this myself, but have had some success with antennas further away.  You may need to experiment to see how far away from the wall is the minimum, but just a very wild guess is maybe something like at least several feet.  I have made some QRP QSO's from AZ, CA, and NV in similar homes to yours, but think the wires were mostly at least 5 feet from walls....signal reports not good, but better than nothing.  Something like your proposed 17 foot wire if it works near your house, is a good length for 15, 20, and 30 meters, and will work with reduced efficiency on 40 meters.  A remote (automatic) antenna tuner at the base of the antenna would be required for 15, 30, and 40 meters for sure, although if you have a built in ATU in your transceiver and a short run of coax, it may do the job with reduced efficiency.  When we lived in apartments, I strung up various wires made of very thin wire, probably 28 ga or smaller, however birds, wind, or whatever took it down a few times a year.  Worked with QRP power, but not sure about 100 watts.   Rick  KL7CW  Palmer, Alaska


Title: RE: Radials and counterpoise for very small yard area
Post by: KF7ZFC on March 27, 2019, 10:26:38 AM
Just bought on EBay 28 gauge white wire will give that a try as per WW7KE and K5LXP.

I have a have a RigExpert AA-30 so I can  tune the antenna. I have a 100 foot run of coax to the antenna.

My Yaesu FT 450D has a auto tuner that can deal with 3:1 swr

Because of how close my neighbor's child's bedroom  is I will be running 50 watts


Title: RE: Radials and counterpoise for very small yard area
Post by: KF7ZFC on March 27, 2019, 10:50:43 AM
Just bought on EBay 28 gauge white wire will give that a try as per WW7KE and K5LXP.

I have a have a RigExpert AA-30 so I can  tune the antenna. I have a 100 foot run of coax to the antenna.

My Yaesu FT 450D has a auto tuner that can deal with 3:1 swr

Because of how close my neighbor's child's bedroom  is I will be running 50 watts


Title: RE: Radials and counterpoise for very small yard area
Post by: KL7CW on March 27, 2019, 11:12:09 AM
Sounds like you are on the right track starting with 50 watts.  I say that since in my experience 5 watts will only rarely cause trouble to consumer devices, but even 100 watts will sometimes cause trouble.  Also I agree with your concern about RF exposure to your neighbor is justified.  My guess is that 28 ga wire will probably handle the power, but this depends upon many factors.         Rick  KL7CW


Title: RE: Radials and counterpoise for very small yard area
Post by: W1VT on March 28, 2019, 07:36:46 AM
https://krupniklaw.com/chapter-3-american-flag-display/
In addition to the federal law on flying the American flag, Arizona has a specific law that requires an association to allow the flying of certain flags on flagpoles on the lot:  the American flag, military flags, the POW/MIA flag, the Arizona state flag, an Arizona Indian nations flag, and the Gadsden flag.  The association shall adopt rules governing the flying of the flag, which may include limiting the member to flying no more than two flags at once and the limiting the height of the flagpole to no more than the height of the rooftop of the member’s home.  However, the association cannot prohibit the installation of a flagpole on a member’s property.


Title: RE: Radials and counterpoise for very small yard area
Post by: KF7ZFC on March 28, 2019, 12:52:19 PM
Zack

The house is owned by my daughter and son-law and I am not sure they would like a flagpole.

Additionally the front yard is not big enough to lay down radials long enough for 20m operation

Steve



Title: RE: Radials and counterpoise for very small yard area
Post by: W1VT on March 28, 2019, 04:38:13 PM
There may be other hams in Arizona that may not be aware of that flagpole law.


Title: RE: Radials and counterpoise for very small yard area
Post by: KL7CW on March 28, 2019, 04:55:09 PM
Just a quick note about on ground or buried radials.  They do not need to be a quarter wavelength long.  In fact it is better and more cost effective to install more, but shorter radials, than a few 17 foot radials which is 1/4 wavelength on 20 meters.  Something like a dozen 8 or 10 foot radials would yield fair results on 20 meters and higher frequencies, and may even work to a certain extent on 40 meters if longer radials are not possible. I am not necessarily recommending a flagpole antenna but we are just trying to have you explore all options.  If you have plastic rain gutters, possibly you could just lay a wire inside the gutter.  I have also just tossed a wire up on roofs and tuned it against ground with an antenna tuner.  However I understand that tile roofs which are common in your area and some composite shingles tend to absorb RF.  I guess you could just try various options.     Good Luck   KL7CW


Title: RE: Radials and counterpoise for very small yard area
Post by: W1BR on March 29, 2019, 07:51:59 AM
The flagpole antennas may be some sort of OCF design similar to a Cushcraft R7.  Although I have a tower and a six band Navassa  JK beam, the backup R7 will work DX.  But again, they are expensive.


Title: RE: Radials and counterpoise for very small yard area
Post by: KF5KWO on March 31, 2019, 03:10:44 PM
Hi Steve,

You and I are in the same boat, my friend.  Stealth ham radio is a reality for many of us. 

I looked up your QTH on Google maps and noted that the current “street view” pic shows some Christmas lights strung up on the eaves of the roof.  I had a wire strung up as a horizontal loop, very much in the same location as those lights and at the same approximate height, all around my house, and could work 40m and 80m quite nicely with it. Quite easy to do. You’d just need to run some twin-lead or similar feedline out through a wall or window and up to the feedpoint. And instead of following the eave to the front door then back out to the garage, just run it above the sidewalk across to the garage. Use a beige-colored insulated wire and it blends right in. I hung mine with little hooks screwed into the wood above it.  Using this method doesn’t require radials.  One thing though: when using it on 20m, it would trip my house alarm!  But 40 and 80 were fine (TS-520SE, 100 watts, MFJ manual tuner).

Granted this is a compromise antenna due to low height and your wish to keep the power output down, but given the lack of trees to provide concealment, this might one of your only alternatives.  And depending on what mode/s you wish to work, 50 watts may be more than enough. You might be in for some QRP operation, or CW and other data modes, rather than SSB or AM.

I also have the MFJ-1786 Magnetic Loop for 30-10m, and use it in conjunction with my current 40m stealth vertical. I’ve had it for about 15 years, can’t complain at all because of what it gives me.

Very best of luck!

73 de Jeff, KF5KWO
Helotes, TX


Title: RE: Radials and counterpoise for very small yard area
Post by: KL7CW on March 31, 2019, 05:16:29 PM
Here are two other ideas to consider, probably neither is a great idea, but should work.  How about installing a good mobile antenna on one of your cars.  If your subdivision does not prevent this.  Then run a small stealth coax out to the car.  Configure it with some type of break away connection, so if the car accidently gets driven, no problem.  Install something better and bigger than a ham stick.  Performance on 20, and 17 should be good, 15, 12, and 10 meters should be excellent, and 40 and 30 meters should be useable, especially if the antenna is at least something like 8 feet or longer and has a low loss loading coil, preferably at least several feet above the base.  Another idea I have considered if I ever need to live in civilization rather than out here in rural Alaska is to buy one of the "portable" basketball hoop supports which I seem to see at about every third house in HOA developments in AZ, CA, etc.  Put it in the driveway, install some hidden radials and an automatic antenna tuner beside your driveway where you have the basketball thing.  I have not measured or modeled them, but if you electrically tied everything in the structure might be equivalent to say a 10 or 12 foot wire, which is probably long enough to work moderately OK on 20 through 10 meters with any good tuner.  I have not tried either of these schemes.  Please do consider going to a local park instead.  Often when we travel or visit outside of Alaska, I just send the girls (wife, daughter, and granddaughter) off on a shopping expedition or visit to a spa for the day while I sit a picnic bench in a park and operate my portable equipment.  It does get a bit rough at times like north of the Arctic circle in Norway in the winter, or on a hot summer day in AZ. Also many parks close at sundown or before 10 PM.  Even a typical urban city park only a hundred meters or so from houses, usually has low or very low receive noise levels. Low power (probably CW) outdoor operation does not appeal to everyone.  When my grandkids were young, often we took them to the park where they would play on the playground or skateboard while I played radio and my wife would knit, read, or play with the grandkids.  Warning, with the present sunspot cycle status being what it is, my park expeditions over the last 5 years have not been as productive as in past decades, both in the "lower 48" and in the UK and Europe, so do not expect a 100 percent success rate.       Cheers,   KL7CW


Title: RE: Radials and counterpoise for very small yard area
Post by: N4NYY on April 01, 2019, 05:56:04 AM
You do not need a solid conductive surface.  Your plan to use chicken wire has a lot of merit.  Check out this web page:

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

Personally, I would opt for a different radiator system, if possible.  How much vertical wire can you run?  There are remote antenna tuners that can handle the matching--not the cheapest solution, I know.

Pete

I'm glad someone asked this as this was something I have always thought about, but never complimented. The question is, if you use chicken wire, how much grid do you need?


Title: RE: Radials and counterpoise for very small yard area
Post by: KD0REQ on April 01, 2019, 02:26:01 PM
how much space you got? ;)

if you think of it as a straight radial field, X*Y. for your favorite bands.  there might be one of those EE "infinite grid of 1 ohm resistors, with one diagonal 1 ohm in the middle. calculate resistance points A and B" issues that makes it look like a perfect counterpoise to everything. this one would not be a washout question for freshmen... but an opportunity to see how good your tuner is.


Title: RE: Radials and counterpoise for very small yard area
Post by: K6PCW on April 29, 2019, 08:20:36 AM
I see it's been nearly a month since anybody's posted on this thread, but the OP and others might enjoy perusing this ham's blog on stealth antennas.  http://www.n6cc.com/tactical-antenna-systems

Some neat ideas, good advice, and enjoyable reading throughout his website.

Good luck!


73 Pete


Title: RE: Radials and counterpoise for very small yard area
Post by: K6PCW on April 30, 2019, 11:18:31 AM
And some more great ideas.  This Florida ham club has does a wonderful job with this antenna publication.
https://www.hamfesters.org/main/wp-content/uploads/2012/07/Stealth-Antenna-Guide.pdf


Title: RE: Radials and counterpoise for very small yard area
Post by: K5TED on May 01, 2019, 08:31:53 PM
Couple of points..

1. MFJ Magloop will outperform the Hamstick hands down, and won't need a ground radial. I have a Hamstick pair for every amateur band and they have not ever outperformed the magloop, or a SuperAntenna MP-1.

2. You have a privacy fence around the property. Use it.

In my backyard, for stealthy operation, I have the MFJ 1786, and a random wire of 120'. The wire is strung along the very top of the privacy fence and fed with a 9:1 unun.

I just recently moved here, and just got my HF station more or less set up., and the results with these antennas is no horrible. DX distance is Spain, EA7JWF on the magloop, and a lot of NVIS sort of contacts on the wire on 75m and 40m.

The wire is, as I mentioned, strung along the top of the fence. There is a chicken wire component..... There is a 24" wide chicken wire along the bottom of the fence, with 12" above ground and 12" covered in river rock and dirt. I silver soldered the ground to the chicken wire in several points and all sems to be working. This weekend I'm putting on a LDG RT-100 tuner to the wire to see if it makes any difference.




Title: RE: Radials and counterpoise for very small yard area
Post by: W8LV on May 07, 2019, 10:44:46 AM
Wire and portable verticals
deliver more watts per investment of resources.
EVERY Time.

While the towers DO look cool in the mags
(I'm surprised that they
don't have a monthly Antenna Centrefold.


Title: RE: Radials and counterpoise for very small yard area
Post by: N9AOP on May 07, 2019, 05:00:55 PM
Oooooh, an antenna centerfold--an idea ahead of its  time.
Art


Title: RE: Radials and counterpoise for very small yard area
Post by: K5WLR on May 07, 2019, 05:37:00 PM
Oooooh, an antenna centerfold--an idea ahead of its  time.
Art

...Rated A!!!  ::)