Limited antenna options; HF still worth exploring?

[n0iop]

I've had my ticket for 30 years and have played around with VHF and UHF. I was responsible for the care and feeding of a 1000 watt broadcast FM plant while in school. My day job has often involved radio with ever higher frequencies. I'm currently working on a millimeter wave project at work.

I've never done much of anything with HF, other than being a guest operator once or twice. It's something I'd like to explore.

The best I can do at my current QTH is a 43' wire antenna up the side of my house (3 stories) and diagonally across the roof, plus ground radials. I'm in a suburban location and expect the noise floor to be high. I'm thinking in terms of 100 watts. I understand what I need to do to make this all work and get it tuned right and keep the RF out of my shack and so on. I also understand how to base load the antenna for 80m and 160m.

My main interests are ragchewing and other longer contacts and a better understanding of propagation and operating technique. I have zero interest in contests. My interest in CW is limited and I realize I will have to upgrade my license to general before proceeding.

My question is whether this is going to be worth it given my limited antenna options and high noise environment. I don't want to build everything up and find out that I can't get out of my own zip code.

Advice welcome.

The 43' wire is the very best I can do for HF for various reasons I don't want to go into. I can do better at 10 meters and up but I'm not sure that's interesting.

Thanks in advance for the replies

 

[prcguy]

A 43ft vertical over a ground plane is a good compromise for 160 through about 17m, then the antenna gets too long and the higher bands go up into the clouds and never come down. The antenna must have an antenna tuner right at the base, otherwise it becomes a 43ft long dummy load.

The ground radials are important needing as much wire as you can lay down and lots of short ones are better than a couple of long ones. A strip or two of 4ft wide chicken wire can make an excellent ground plane for these.

I would be concerned with the very close proximity to the house with wiring in the walls, metal flashing, etc. Is the house stucco? That will have a metal lath shield beneath the stucco.

I have a 43ft vertical by DX Engineering planted 125ft away from a house fed with LMR400 and 1,000ft of wire under it or 30 something radials about 30ft long each and it works quite well. The stock configuration included a 4:1 balun and its performance with that was not worth the cost and effort to put it all up. After swapping the balun for an SGC auto tuner the antenna came alive and has been a great performer.

Since you are considering a wire version, you can easily put something in temporarily to test then build it out if the performance meets your expectations.

I've had my ticket for 30 years and have played around with VHF and UHF. I was responsible for the care and feeding of a 1000 watt broadcast FM plant while in school. My day job has often involved radio with ever higher frequencies. I'm currently working on a millimeter wave project at work.

I've never done much of anything with HF, other than being a guest operator once or twice. It's something I'd like to explore.

The best I can do at my current QTH is a 43' wire antenna up the side of my house (3 stories) and diagonally across the roof, plus ground radials. I'm in a suburban location and expect the noise floor to be high. I'm thinking in terms of 100 watts. I understand what I need to do to make this all work and get it tuned right and keep the RF out of my shack and so on. I also understand how to base load the antenna for 80m and 160m.

My main interests are ragchewing and other longer contacts and a better understanding of propagation and operating technique. I have zero interest in contests. My interest in CW is limited and I realize I will have to upgrade my license to general before proceeding.

My question is whether this is going to be worth it given my limited antenna options and high noise environment. I don't want to build everything up and find out that I can't get out of my own zip code.

Advice welcome.

The 43' wire is the very best I can do for HF for various reasons I don't want to go into. I can do better at 10 meters and up but I'm not sure that's interesting.

Thanks in advance for the replies

 

[ParanoidAndroid]

Just wait until the metamaterial based antennas start working their way down into amateur radio. It's still a military/commercial only playing field right now, but that is quickly changing with guys like fractal antenna systems and others...

An HF antenna that is 1/10th the size of the standard half wave length we commonly deploy, can now out perform such antennas with the advancements made in the metamaterial field. The old belief that you could never achieve low SWR, wide bandwidth, and small size, is no longer true.

 

[n0iop]

Thanks for the reply. The wall construction is drywall, 2x6 frame, fiberglass insulation, MDF sheathing, and vinyl siding. There is an aluminum downspout running parallel about 6 feet away. I believe that will make the pattern a little asymmetrical without doing much else. There is aluminum gutter that crosses the proposed wire, I can maintain several inches spacing. Should have little effect. Otherwise not much in the walls, no plumbing or electrical wiring in this area.

Advice noted regarding 15m up. I can easily put up monoband antennas for 11, 10, and 6 meters if these prove to be of interest. I doubt if 15m and 12m will be anything compelling for me in the next few years and after that we'll probably end up moving.

TNX 73

 

[zz0468]

What sort of space do you have for a dipole? An open wire fed dipole used with a tuner eliminates the need for a really good RF ground/counterpoise.

Depending on how long the elements are, it could easily load up on 80 meters. I use a dipole that's 43' on each leg, and it gets out fine on 160.

The dipole doesn't have to be linear in construction, a vee, inverted vee, or legs bending to fit the yard work fine. Just use balanced line and a tuner, and it'll get out.

 

[n0iop]

What sort of space do you have for a dipole? An open wire fed dipole used with a tuner eliminates the need for a really good RF ground/counterpoise.

Depending on how long the elements are, it could easily load up on 80 meters. I use a dipole that's 43' on each leg, and it gets out fine on 160.

Thanks for the suggestion. Due to zoning restrictions, the size of the lot, placement of trees, siting of the house, aluminum gutters, roofline, and other factors, I can't put up a horizontal dipole with a total length much greater than 20 feet.

Couterpoise radials, on the other hand, aren't a major problem for me.

 

[K4EET]

With respect to who you can talk to, you will be surprised what your proposed antenna system and 100 watts will do. QSOs around the world will be possible given the right band conditions and frequency used. I have worked New Zealand with an antenna that was in my attic and only 15 feet long on each side of the dipole with 5 watts of power.

One thing to keep in mind is that we are currently at the lowest point of the solar cycle. The next peak will not be until 2024. Here are some weblinks on the subject:

SOLAR PREDICTION
https://solarscience.msfc.nasa.gov/predict.shtml

SOLAR CYCLE 24 STATUS AND SOLAR CYCLE 25 UPCOMING FORECAST
https://www.swpc.noaa.gov/news/solar-cycle-24-status-and-solar-cycle-25-upcoming-forecast

WAITING FOR THE NEXT SUNSPOT CYCLE: 2019-2030
https://www.huffingtonpost.com/dr-sten-odenwald/waiting-for-the-next-suns_b_11812282.html

Since we are at a solar minimum, propagation conditions are currently at their worst. But what goes down must go up. Right? LOL!

73, Dave K4EET

 

[TheSpaceMann]

An end fed might work well in your situation!

 

[nanZor]

I wish I had that kind of space!

I'd put it up, and then if household noise is an issue, you may want to look at the Timewave ANC4, or MFJ 1026 noise cancelling phasing units. The built in whip may be just enough for the sense antenna too.

 

[wyShack]

I am not fond of verticals as they eliminate NVIS- which is the most used propagation mode for 80 and 40 although many don't realize it. Most regional work (say out to 700 miles) is NVIS. I would run a horizontal end fed wire as long as I could and use a 9:1 transformer. Feed with coax and use a tuner. A 20 foot wire and 50-100 watts will work 40,30 and 20 meters with satisfactory results. I would cut dipoles for 10-17 meter. Not much happening there with the sunspots down. 40 meters at night and 20 during the day will give the most distance with 30 meters (either CW or digital) also being usable.

You will have to listen around and 'work' for DX but will be surprised by the range you will have and listening will let you learn about propagation. After a few months, you will learn when to listen for DX. The 'compromise' antenna means you can't compete with beams -but you can enjoy HF.

73

 

[n0iop]

Thanks for the supportive, insightful comments.

I would run a horizontal end fed wire as long as I could and use a 9:1 transformer. Feed with coax and use a tuner. A 20 foot wire and 50-100 watts will work 40,30 and 20 meters with satisfactory results.

Due to zoning and other factors my ability to install a horizontal antenna is limited. Since suggestions to install something other than a vertical keep coming in, here is what is possible:

* I can install any type of citizens' band antenna that I wish. Since any citizen's band antenna is inherently dual use and can be tuned for 10 meters, I can pretty much cover this band. Unfortunately, 10 meters isn't going to be open often enough to matter for a few years.

* I can install a wire antenna up to 16 feet total length on my elevated deck, and no one will know or care. This provides options for 6 meters.

* I can install a wire antenna up to around 40' total length, horizontally on my house, where it would be parallel to the aluminum rain gutters, and maybe 18 feet above ground. I believe the rain gutters will act as a reflector to some degree. I am reluctant to run an end fed antenna in this location because I have no idea where the RF will go without a well-defined counterpoise. With a dipole I'm limited to, well, 20 meters and up or so.

* I can find places to put 2m and 440 Mhz antenans, if I want to, because they are so small and no one will know or care.

Based on this, I think the 43' vertical is simply the best I can do for HF, at least for 160m-20m. I can put it on my house, cross the gutter at right angles, and put in ground radials. I don't think anyone will know what it is or care why it is there.

 

[prcguy]

The vertical sounds like a good option if everything else fails and it will get you on the air on a number of bands. The rain gutter and downspout could be a blessing in disguise. If its all aluminum and is of reasonable length and has a aluminum downspout you could feed it against a ground plane.

Worst case you might have to run along its length with an 1/8" drill and some pop rivets or sheet metal screws to make sure its got continuous continuity. Then stick an auto tuner at ground level at the downspout and run that against some ground radials or some chicken wire as a counterpoise.

Thanks for the supportive, insightful comments.



Due to zoning and other factors my ability to install a horizontal antenna is limited. Since suggestions to install something other than a vertical keep coming in, here is what is possible:

* I can install any type of citizens' band antenna that I wish. Since any citizen's band antenna is inherently dual use and can be tuned for 10 meters, I can pretty much cover this band. Unfortunately, 10 meters isn't going to be open often enough to matter for a few years.

* I can install a wire antenna up to 16 feet total length on my elevated deck, and no one will know or care. This provides options for 6 meters.

* I can install a wire antenna up to around 40' total length, horizontally on my house, where it would be parallel to the aluminum rain gutters, and maybe 18 feet above ground. I believe the rain gutters will act as a reflector to some degree. I am reluctant to run an end fed antenna in this location because I have no idea where the RF will go without a well-defined counterpoise. With a dipole I'm limited to, well, 20 meters and up or so.

* I can find places to put 2m and 440 Mhz antenans, if I want to, because they are so small and no one will know or care.

Based on this, I think the 43' vertical is simply the best I can do for HF, at least for 160m-20m. I can put it on my house, cross the gutter at right angles, and put in ground radials. I don't think anyone will know what it is or care why it is there.

 

[WRCM]

I would definitely load up the downspout against a ground screen and make some contacts. The inverted-L you describe will work just fine, too.

Antenna experimentation is at least half the fun of HF.

 

[ka3jjz]

There are many transmitting loops that might also be something to consider. Alpha Antennas, Chameleon, and the W4OP antenna are just a few examples, and there's a Facebook group (Magnetic Loop Antennas) that's all about homebrewing.

All of this is linked on our Loops wiki page...

Loops - The RadioReference Wiki

Mike

 

[jim202]

What might be of interest is the use of a good balun at the center of a wire dipole. I have tried a number of different brands. I have found that the MFJ units don't cut the noise down as much as other vendor brands do. Not sure why this is so, but that is what I have found on several of my dipole installations.

Ask around and get feedback from others using balun units on their dipole antennas.