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eHam Forums => Antenna Restrictions => Topic started by: KF5YTK on October 20, 2021, 12:17:23 PM

Title: Multiband antenna for limited space!!
Post by: KF5YTK on October 20, 2021, 12:17:23 PM
Been a while since I have posted, but I wanted to pick my fellow hams minds for a moment if I could.

I have moved into a HOA community (temporarily)and it has limited my antenna selection down pretty good. unfortunately I only have a push up pole with a 2 meter antenna on it that I scope up and down here and there just took keep up with my local community (60 mile radius).

I use to be a avid 160 meter talker (1916) and I don’t have the room to properly get back on that band but would like to at least talk on 80/40 meters to keep my HF friends entertained again.. My question is what is the best antenna I can use without having my HOA up my you know what so I can get back on the air again and have a quality antenna setup! I do not have any trees and my fenced in back yard is about 30 yards long and 10 yards wide. I’m just looking for recommendations and appreciate all that can help!
Title: Re: Multiband antenna for limited space!!
Post by: AA4PB on October 20, 2021, 12:42:48 PM
On 40M I used a dipole made from two Hamsticks mounted end to end. They worked pretty well as long as I got them at least 10-15 feet above ground. 80M will be a bit more of a challenge. I was running 5W CW at the time. It could be something that you set up when you want to use it and lay down on the ground (out of sight) when it is not in use.
 
Title: Re: Multiband antenna for limited space!!
Post by: N6MST on October 20, 2021, 12:46:01 PM
Since you're talking 80/40 a ground-mounted, trapped vertical could be perfect for you. Using a tilting mount you could have the antenna folded down during the day and then just flip it up at night when 80 and 40 are kicking. Given the provided dimension you have plenty of room for a decent radial field. A coil-shortened and trapped vertical could be built in a manageable size.

The other idea is also a vertical but maybe the well-known 43 foot vertical might be a contender. They aren't necessarily amazing but it would get you on the air alright.

I assume you haven't updated your license since you moved? Your current QRZ address shows a bunch of wonderful trees!
Title: Re: Multiband antenna for limited space!!
Post by: KF5YTK on October 20, 2021, 12:52:50 PM
Yes, I have not made the address change yet and am actually fixing to do that this week. My last location was absolutely perfect and I had a nice selection of wire antennas tossed up in a 160 slanted inverted V and the others were inverted Vs!

I like the idea of using a dipole and maybe laying it down when the time comes to do so!
Title: Re: Multiband antenna for limited space!!
Post by: WB6BYU on October 20, 2021, 01:22:16 PM
A lot is going to depend on the exact rules of the HOA, and what you
think you can get away with, as well as the dimensions of your
house, the type of roofing, etc.

My back yard is about the same width (but barely 20 feet deep, and
filled with plants).  I got a telescoping mast that attaches to the center
of the back fence to make it easy to run it up and down.  (Technically,
if it were mounted on the other side of the fence, it would not be
covered by the HOA!)  I can string up full-sized dipoles for 40m and
a half size (coil loaded) dipole for 80m that is about the same size as
a 40m dipole.  I could also use a full-size 80m dipole with the ends
running along the side fences (the bent shape may require a bit more
wire).  For 160m, you could run a dipole to the corners of the fence,
insert loading coils, then run the ends along the side fences.  You'll
probably need a shunt coil at the feedpoint, especially on 160m, as
the impedance likely will be low.

Using a dipole, even if it isn't very high, probably works better for
NVIS contacts in the local area - at least out to a couple hundred
miles, where a vertical tends to have a null in the pattern (although
using an "inverted L" may fill in the null somewhat).  On 160m, you
will have to see whether NVIS or ground wave (which requires vertical
polarization) works better to the stations you want to work.

I do have a dipole on the roof for 40m, and am planning to extend it
to a "bow tie loop" to cover down to 80m - that might cover 160m when
fed with balanced line to a tuner.  The antenna wire is #26 stranded,
with brown/green/black striped insulation, tied off with black micro cord
on the ends, making it virtually invisible above the roofline (except when
we get frost or ice on it, or the sun glints on it just right).  I used to just
lay my wire antennas on the roof and tuck them under the corners of
the shingles, but asphalt shingles are much more lossy than the old
wooden ones.  My current plan is to add extensions to my roof vents
(and add dummy ones where needed) to hold the wires up above the
roof somewhat.

Otherwise, I've also used a loop around the house, stapled to the back
side of the fascia boards under the eaves.  You can put it up when you are
up on a ladder stringing Christmas lights and bring the feedline in through
the attic - it will be invisible to anyone who isn't looking right up under
the eaves.  You can then feed it with a tuner, or make it a dipole and
add loading coils if needed.

None of these are necessarily ideal, but they have all worked at various times.
Title: Re: Multiband antenna for limited space!!
Post by: W4HRL on October 20, 2021, 05:42:16 PM
I would suggest looking into EFHW (End Fed Half Wave) mounted as an Inverted - L.  I would mount the 49:1 box about three to four feet above the ground and run the vertical part of the L up a Spiderbeam HD 12-meter pole (or equivalent) and the rest of the antenna as needed (up, down, zig-zagged, whatever) to fit the available space to reach Spiderbeam pole #2.

Spiderbeam poles http://www.spiderbeam.us/index.php?cat=c2_Fiberglass%20Poles.html&XTCsid=c31e93e2085dcc62c2f54c5b35486013

These 12-meter Spiderbeam poles have become my "tree substitute" when needed.  Although they are 12 segment poles, I usually only use the bottom 10 segments to give a "less flexible" setup. The top 2 segments are pretty thin and "whippy".

Good luck on finding a workable solution to get you back on the air.

W4HRL
Poquoson VA

Title: Re: Multiband antenna for limited space!!
Post by: KF5YTK on October 20, 2021, 06:25:21 PM
A lot of great recommendations that has absolutely helped me come up with a solution to my problem! I always like to brain storm with other Hams just so I can have fresh ideas.
Title: Re: Multiband antenna for limited space!!
Post by: KE0VT on October 20, 2021, 11:08:55 PM
I am using a Broadband terminated dipole. I have worked Slovenia and Spain, Japan and all over the US and Canada. Even with the current band conditions.
 You lose about 70% of the input power so get out about 25-30 watts. Mine is up 22' in the attic. The 16:1 balun and the resistor, 1K ohms, are both available from Palomar Engineers.
I used 14 gauge coated wire. I drilled holes in a "cut card" the kind you see in blackjack or other card games. Inexpensive and tough. I also cut them in 3rds. One pack did it all.
Signal reports are mostly 5-5 to 5-7 but I have had 5-9 and one 20 over 5-9 on 12 meters. It will work 6-160. SWR 1.6:1 or better everywhere except 6 meters it is about 2.27:1 but
the tuner in the 590SG handles it beautifully. Just be sure both legs are very close to the same length. The shape isn't critical, you can bend it around corners or in my case I have
a rectangular attic. Get it as high as you can.

I am good on QRZ if you want to talk.

73

KE0VT
Title: Re: Multiband antenna for limited space!!
Post by: W4FID on October 21, 2021, 01:54:07 AM
Been a while since I have posted, but I wanted to pick my fellow hams minds for a moment if I could.

I have moved into a HOA community (temporarily)and it has limited my antenna selection down pretty good. unfortunately I only have a push up pole with a 2 meter antenna on it that I scope up and down here and there just took keep up with my local community (60 mile radius).

I use to be a avid 160 meter talker (1916) and I don’t have the room to properly get back on that band but would like to at least talk on 80/40 meters to keep my HF friends entertained again.. My question is what is the best antenna I can use without having my HOA up my you know what so I can get back on the air again and have a quality antenna setup! I do not have any trees and my fenced in back yard is about 30 yards long and 10 yards wide. I’m just looking for recommendations and appreciate all that can help!

Ultimax makes several models/lengths of balun end fed wire antennas. They are in Ocala, FL and can be found advertising or via a Google. I have one of their 31 foot ones in my attic at 15 feet. It does quite well and is completly HOA invisible. I also have a 24 foot one as a sloper to a 22 foot push up mast outside that is used when needed and hidden when not. It too works well.
Title: Re: Multiband antenna for limited space!!
Post by: W4FID on October 21, 2021, 01:55:33 AM
Ultimax makes several models/lengths of balun end fed wire antennas. They are in Ocala, FL and can be found advertising or via a Google. I have one of their 31 foot ones in my attic at 15 feet. It does quite well and is completly HOA invisible. I also have a 24 foot one as a sloper to a 22 foot push up mast outside that is used when needed and hidden when not. It too works well.
Title: Re: Multiband antenna for limited space!!
Post by: W9IQ on October 21, 2021, 05:37:55 AM
Ultimax makes several models/lengths of balun end fed wire antennas. They are in Ocala, FL and can be found advertising or via a Google. I have one of their 31 foot ones in my attic at 15 feet. It does quite well and is completly HOA invisible. I also have a 24 foot one as a sloper to a 22 foot push up mast outside that is used when needed and hidden when not. It too works well.

Most likely an autotransformer fed antenna that would do well with the addition of a balun/common mode choke?

- Glenn W9IQ
Title: Re: Multiband antenna for limited space!!
Post by: KB0QIP on October 24, 2021, 05:53:58 PM
Overthe weekend a friend went and did a Parks on the Air. He used a new antenna. It was a simple 102 in colaplasable whip and a adjustable coil on a simple tripod.  It worked all over the country, into canada. There were some cub scouts that came by and we got one young 7 yr old on the radio with a wonderful gent in Scotland. This was QRP. Blew me away. I got home and looked it up. Wolf River Coils Silver Bullet 1000 TIA {Take It With you}. Take a look, it may work for you. I'm ordering soon.
Title: Re: Multiband antenna for limited space!!
Post by: N9SA on December 20, 2021, 06:28:56 PM
Put a flagpole antenna in the backyard.  I'm just getting back into the hobby after moving back to the US from Europe.  I foolishly moved into an HOA and only have a postage stamp sized back yard.  I put up the ZeroFive flagpole and only have about 10 radials put down so far.  I use a Palstar HF Auto and can work 80 meters and up.  I can load 160 meters but don't want take the chance of melting the transformer. 

I don't think the HOA can turn your request to put one up.
Title: Re: Multiband antenna for limited space!!
Post by: N1UR on December 26, 2021, 04:49:07 PM
When I lived for a while in an HOA in Texas, I wanted to put up some vertical wires in the trees.  There were a number of 70 footers.  I had about 1/4 acre that had 3 of them in the back.  I happen to notice that there we numerous people that had run electrical wires up tries with lights that lit up the upper portion at night.  So I decided that wires were wires and decided to put up a multiband vertical dipole on 10 - 40 and one for 80 and one for 160. 

I had a visit from the HOA police.  They wanted me to take down the antenna wires.  I said as soon as you tell everyone with wires up their trees with lights to do so, I will comply.  They went away and I never heard from them again. 

I lived their 3 years and did some reasonable DXing using those antennas.

Don't assume you can't put something up.  Look closely at what is being allowed - like flagpoles, christmas lights, etc.  If they can do it, you can do it, and a wire is a wire - a pole is a pole.

Ed  N1UR
Title: Re: Multiband antenna for limited space!!
Post by: KF5YTK on February 06, 2022, 07:15:08 PM
Thank you all so much for the recommendations !! I have had a great amount of ideas come together for me to execute something for my situation.

I also want to thank “KE0VT” for the great letter I received in the mail pertaining to my question, you were a lot of help!!!
Title: Re: Multiband antenna for limited space!!
Post by: KA4VNM on February 28, 2022, 07:57:03 AM
It is interesting to note that many HOA's have not updated the OTA rules changes the FCC rewrote years ago. That is a door that in many situations might open up discussions with the HOA's as to accommodations which mimic or emulate TV/FM antennas. Most 2-440 and even 6 meter antennas look like TV aerials.  Something being better than nothing. My HOA is in VA and they actually incorporated the new statute into the HOA rules.  Sometimes just talking it through works.
Title: Re: Multiband antenna for limited space!!
Post by: KK4GMU on July 22, 2022, 11:23:51 AM
I ended up installing a G5RV Junior flat on my asphalt shingle roof.  The roof pitch faces the back yard, so not seen from the street.  The dipole connection is around 5 feet higher than the ends of the dipole, so it is roughly in the shape of an inverted V.

The SWRs are within non-tuner range on parts of 10 and 20 meters.

I haven't yet broadcasted on it.
Title: Re: Multiband antenna for limited space!!
Post by: WB6BYU on July 22, 2022, 08:21:11 PM
Adding an extra 5’ or 10’ coax extension to your
cute t feedline may permit a match - you’ll have to
experiment with the length.

It also depends on your tuner, but there are a number
of ways around the problem.
Title: Re: Multiband antenna for limited space!!
Post by: KE0VT on July 22, 2022, 10:14:53 PM
I have a broad-banded terminated dipole in the attic. 100W in and about 25 out. SWR is 1.6:1 or better from 10-160, 2.36:1 on 6 meters. You generally don't get high signal reports
but I have worked Spain, Italy, Slovenia and near Sao Paulo, Brazil. Inexpensive to build. Has very good ears but can't always work those you hear. It can be zig zagged around, just
keep each leg very close to the same length. Mine is 55' per leg. I am in Colorado. Longest contact so far is 5700 miles to Japan. I use a 1K ohm resistor. I also have Isotron
antennas on 6, 10, 15 and 20M. Despite what some think of the Isotrons they do work.   73
Title: Re: Multiband antenna for limited space!!
Post by: KK4GMU on July 24, 2022, 08:24:44 AM
... but asphalt shingles are much more lossy than the old
wooden ones. 
Can you elaborate a bit on asphalt shingles being lossy when the wire is layed down directly on the top of it?  Is there a typical amount of lossiness (measurable how?) compared to the wire being 1" or 1' or 5 feet above the shingles?

If lossiness is significant when the wire is layed down on the asphalt shingle, my plan B would be to mount the center of my G5RV Junior on my retractable pole, a foot (or more????) below my 2 meter/70cm vertical.
Title: Re: Multiband antenna for limited space!!
Post by: WB6BYU on July 25, 2022, 01:52:54 PM
Quote from: KK4GMU
Quote from: WB6BYU
... but asphalt shingles are much more lossy than the old
wooden ones. 

Can you elaborate a bit on asphalt shingles being lossy when the wire is layed down directly on the top of it?  Is there a typical amount of lossiness (measurable how?) compared to the wire being 1" or 1' or 5 feet above the shingles?...




I don't have accurate numbers.

There are two effects:  the dielectric loading, where the antenna
resonates at a lower frequency when close to the roof, and
the losses in the material itself.  The first one is easier to measure.

I've installed a 40m loop around the roof at several houses, often
finding the resulting antenna resonated significantly lower in
frequency than I had expected.  The loop at this house was about
5.5 MHz, with most of the wire laying on the shingles.   Then I
tried propping it up on a dozen plastic pint refrigerator containers,
perhaps 4" or so (although the wire still touched the roof in places
in between them).  That raised the frequency to 6 MHz or so.

It still didn't seem work very well, but I was plagued with noise
so I didn't get to try it out much.  Now my noise has (mostly)
disappeared, and I have a 40m doublet fed with 300 ohm twinlead,
about 2 - 3 feet above the roof.  Still doesn't work very well, but
part of that problem is due to losses in the tuner (the impedance
at the end of the feedline on 20m is about 5 ohms, which is not
good for tuner efficiency).

By contrast, when I've done that with wood shingles, they were
relatively transparent to RF (at least when dry), and I've had
good results just tucking the wires under the corners of the shingles.


It would, however, be an interesting study.  I think erecting a loop or
dipole on the roof and measuring the impedance over frequency,
possibly at different heights above the roof, might give us some
more details to work with.

Some day...


Of course, there are a lot of details that will affect the results, like
the use of foil-backed insulation beneath the shingles, the actual
composition of the roofing, other wiring in the attic, etc.
My guess is that a foot or so off the roof would make a significant
difference.