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An Idea to Improve Ground Conductivity
Charles Winkler (KC4GMY)
on
July 28, 2007
View comments about this article!
KC4GMY Seeks to Improve Ground Conductivity
Hams are known for their experimenting (even hair-brained ideas) nature and I am sure many great antennas and station accessories have sprang fourth from this spirit of curiosity.
I recently had one of these idea come about after installing my G5RV and using a broadcast spreader all in the same day.
I was putting the spreader back in the basement when I happened to see a half-pint carton of BBs my son had left nearby. Simultaneously looking at the carton and the spreader, the cogs started turning and I was soon imagining myself dumping those BBs into the spreader and sprinkling the ground under my G5RV in improve the soil conductivity.
I surmise that the BBs would sink into this soil after a few rains and lawn cuttings. They are copper coated steel so it would probably take a while for them to rust.
I also researched and found that 40 pounds of zinc coated steel shot sells for around $60.00 (from reloading suppliers), which is more cost effective than buying BBs.
I passed this idea along on the HF bands and most hams seem to think that it would help the antenna perform better (especially on 40 meters and below) and at worst, do no harm. I am seeking comments on this soil doping idea.
Are there any environmental concerns?
How many BBs or shot per square foot?
Is it even worth the effort?
This article has expired. No more comments may be added.
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An Idea to Improve Ground Conductivity
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by KC8VWM on July 28, 2007
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I am thinking that placing an ordinary wire on the ground under your antenna would have a similar effect or improvement. Might be cheaper too.
The only environmental concerns I can thing of is birds trying to eat the pellets off the ground?
BB pellet coverage rate? Hmmm.. Good question. I can see how the density of the pellets might affect how well the idea would work. Wouldn't more be better? I suppose that would depend on the cost analysis vs. the improved antenna efficiency factor involved not sure.
I am wondering how you would set it up in EZNEC to show how this would work in an antenna modeling scenario.
You might be on to something. Perhaps it's not directly related to your specific signal improvement idea, but this idea might lead to improve another similarly related problem in completely different set of circumstances for example.
Let's see what others have to say and keep experimenting!
Good thinking, we need more of this.
73 de Charles - KC8VWM
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RE: An Idea to Improve Ground Conductivity
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by KB9CRY on July 28, 2007
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even hair-brained ideas !!!
You said it.
Just hook up the rig and operate. Leave the BBs alone.
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An Idea to Improve Ground Conductivity
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by EPERK on July 28, 2007
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Leave it alone. Take it from an old broadcast engineer, bb's will not get the job done and will make it harder for the robins to fly
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An Idea to Improve Ground Conductivity
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by W8JI on July 28, 2007
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There would be very little change with BB's since they are very very small compared to the wavelength, unless you used so many BB's that they touched and formed a solid connected sheet. Even if you used so many BB's you had 50% coverage there wouldn't be much change.
Think of it this way. Each BB replaces an equal length of soil with its lower resistance. If you used so many BB's you replaced 50% of the soil with BB's, you ONLY double conductivity.
Now look at a radial. A grid of 50 radials 1/4 wave long spaced .05 wavelengths at the open ends makes the soil look nearly like a perfect solid conductive sheet. The increase in conductivity is now thousands of times, not just double like the 50% BB coverage.
It would be better for the radio to sprinkle a light coating of rock salt, but then you would alter the environment.
The safest, cheapest, and most effective thing to do would be to install radials.
That's why people do it that way, and have done so for many years.
73 Tom
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RE: An Idea to Improve Ground Conductivity
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by K9DMW on July 28, 2007
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Bad idea when mowing. You don't flying projectiles coming out of your mower!
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RE: An Idea to Improve Ground Conductivity
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by JF1AFQ on July 28, 2007
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As a new ham, I feel the elmers here got the key issues covered. Just one more thing. The G5RV near my shack is a ladder-fed dipole. Only when used on 160m (as a top-loaded vertical) the MFJ-1778 manual requires a ground screen or radial ground system.
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An Idea to Improve Ground Conductivity
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by KE5MVD on July 28, 2007
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I heard about a couple of old boys were frog gigging and there head lights stoped working they checked the fuse one was bad but they did not have a replacement so they used an unfired twenty two bullet,take a wild guess on what happened.
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RE: An Idea to Improve Ground Conductivity
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by KC4GMY on July 28, 2007
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Here is some good information on soil conductivity:
http://www.fcc.gov/mb/audio/m3/
Download 47 CFR 73.190 and change the extension to .pdf to see a larger map with soil conductivity numbers. AM broadcasters use these maps to predict propagation.
From reading other articles on the net, it seems that soil conductivity matters most with ground waves. The higher the number and the more land area, the better the reception.
The soil (red clay) in this area has a value of 2, which probably explains my poor reception on AM broadcast bands.
Another good article here by W4RNL:
http://www.cebik.com/wire/cb.html
He has a very nice chart comparing antenna height and soil conductivity with different NVIS Dipoles. According to the chart, higher soil conductivity benefits are realized most at lower antenna heights.
So it seems the most effective solution for my antenna is to increase the height!
Charles - KC4GMY
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RE: An Idea to Improve Ground Conductivity
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by W3LK on July 28, 2007
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Why is this an article? It would have been better as a question in one of the forums.
It's still a hair-brained idea.
73,
Lon - W3LK
Naugatuck, Connecticut
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RE: An Idea to Improve Ground Conductivity
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by W9OY on July 28, 2007
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nothing like a good dose of copper ions to kill the plants.
73 W9OY
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RE: An Idea to Improve Ground Conductivity
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by N4KC on July 28, 2007
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I had to double check to make sure this was not an April 1 article. About the only way to effectively change your ground conductivity (even if that would help with a G5RV) would be to flood your lot with salt water...on a regular basis. Not good for Bermuda grass but you might have a secondary source of income by farming shrimp or oysters.
Far more practical--if you have an antenna that needs a mirroring ground plane--to do a decent radial system made up of conductive wire, strap, or wire mesh.
BBs? BS! ;-) But thanks for thinking.
73,
Don N4KC
www.n4kc.com
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RE: An Idea to Improve Ground Conductivity
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by KC8VWM on July 28, 2007
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According to the chart, higher soil conductivity benefits are realized most at lower antenna heights.
So it seems the most effective solution for my antenna is to increase the height!
Charles - KC4GMY
----
Generally speaking that would be true if you were working above 40 meters and desired to work a lot of DX and didn't wish to take advantage of any NVIS propagation.
I'm not sure how how Cebik defines "lower heights" exactly since a 160m antenna located at 100 feet above the ground would be considered as installed very low to the ground in the overall wavelength of things.
The general rule and as I understand it, NVIS prorogation is generally not applicable to operating frequencies below 40 meters anyways, so placing your antenna at a particular height above the ground with respect to the soil below to take advantage of any NVIS propagation on 160m for example, may not be the chief consideration in that particular scenario.
However seeking to place the antenna at an optimum height with respect to the soil to take advantage of optimum DX take of angles (TOA) on 160m for example may be the main consideration in this particular instance.
I welcome any corrections or follow up thoughts.
73 de Charles - KC8VWM
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RE: An Idea to Improve Ground Conductivity
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by W4VR on July 28, 2007
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If you can find a way to strap all those bb's together it might work. Otherwise, don't waste your time spreading bb's all over your yard. You may have better luck if you solder all those bb's together in a straight line and use the assembly as a dipole.
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RE: An Idea to Improve Ground Conductivity
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by KR4WM on July 28, 2007
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I think you'd have better results if you poured rock salt all over your yard. In short order you'd have better ground conductivity, and no grass left to mow, leaving more time to operate your radio- a win-win combination! <GRIN> -KR4WM
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RE: An Idea to Improve Ground Conductivity
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by K0BG on July 28, 2007
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When I worked at CW Electronics in Denver, during the mid 70s, one of my customers brought me a gallon jug of iron filings ground off from brake drums. He swore they helped the ground plane around his vertical.
I've had other people tell me they've sprinkled copper sulphate around the yard for the same reason.
Personally, I think they're both hair brained ideas.
As for BBs, well....
Alan, KØBG
www.k0bg.com
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An Idea to Improve Ground Conductivity
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by KG4YTL on July 28, 2007
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I don't think it is a crazy idea. Radials don't even need to be attached to the feedline for them to work. I could see that enough pieces of random length pieces of metal would act as a grid system. I would envision metal shavings acting better than points (BBs). Something like aluminum shavings would be better than steel (rust) or copper (chemical interaction with lawn maybe.)
Arguing by extremes:
If you covered the entire yard with BBs, you would have a continuous sheet of metal which would be great. I don't know what percentage you would have to cover to equal 4 radials though.
I agree with others that it is not needed for a horizontal antenna though. Height is the main thing for improving the system. The soil really only makes a difference with vertical systems.
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RE: An Idea to Improve Ground Conductivity
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by W7ETA on July 28, 2007
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To make it worse, some might argue you want to REDUCE soil conductivety under a horizontal antenna.
My rule of thumb is that if I come up with a GREAT! simple idea, that no one else has though of, I don't understand something, or I am missing something important.
73
Bob
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RE: An Idea to Improve Ground Conductivity
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by KF4HR on July 28, 2007
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I see lots of blue colored copper-oxided BB's in your future! :^)
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RE: An Idea to Improve Ground Conductivity
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by KE3WD on July 28, 2007
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Just a weird-case worst-case scenario:
Let's say you actually sowed thousands of copper plated BBs into your yard.
They, of course, will start to corrode almost immediately in the elements.
Any two or more BBs in contact with each other could conceivably end up stuck together by corrosion, rust, etc. -- and form a dissimilar junction.
Thousands of diode-like dissimilar junctions on the ground under your antenna.
Noise machine.
But your neighbors would likely be intrigued by your "talking yard".
Some places I used to work in, they had salted the concrete in the walls with hundreds of thousands of diode junctions to block RF penetration spying. The ultimate passive Noise Machine.
Your BB salted backyard wouldn't be too far behind.
.
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RE: An Idea to Improve Ground Conductivity
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by VK2GWK on July 28, 2007
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What intrigues me most is: "What the heck is a BB???" I tried to look it up and found:
Brigitte Bardot,
Bayerische Bauernbund
Batman Beyond
Besty Boys
Best Buy
and many others but nothing I would like to spread under my antenna (although Brigitte Bardot might be rather decorative in my back yard).
Se, please help me out....
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RE: An Idea to Improve Ground Conductivity
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by KB9CRY on July 28, 2007
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BBs are little steel balls larger than shotgun shell shot that are used in air pump BB guns. Every kid got a BB gun back in the old days.
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RE: An Idea to Improve Ground Conductivity
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by KB9CRY on July 28, 2007
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Better use for the BBs would be to melt them down and recast them as tower sections so you can get that antenna up higher. The G5RV is a good 20M antenna and a total compromise on the other bands it is designed to work.
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An Idea to Improve Ground Conductivity
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by KD0XX on July 28, 2007
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It might be a bad idea, who really knows?
But thinking "OUTSIDE THE BOX" has brought about MANY
discoveries in the past.
Keep it up!
RoD
KD0XX
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An Idea to Improve Ground Conductivity
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by WB6MMJ on July 28, 2007
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It really doesn`t sound like the way to go. I give you allot of credit for trying to come up with something different that would help the grounding problem though. It seems most people don`t want to brain-storm ideas much anymore.
I do think for the money it would cost for shot or BB`s, and the end results, you would be much better off using wire buried in the ground or wire mesh.
First, think about how much area a wire would be touching if buried compared to BB`s. and it would be connected to the ground of the antenna where the BB`s wouldn`t. Area and ground connection, I believe, is the key here.
When you have ground, earth, that doesn`t conduct well you have to use wire or a mesh. BB`s and shot would not be connected electrically together to really do anything.
Keep thinking of new things. It is always fun and it also keeps the mind sharp.
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RE: An Idea to Improve Ground Conductivity
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by W8JI on July 28, 2007
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There are a few myths being propagated here.
The first one is that a ground screen or good ground only helps a vertical, and a dipole doesn't need a ground. Not quite true.
A dipole or any other antenna obtains about 6dB gain from the presence of earth. This is why my 40 meter 3 element Yagi has about 15dBi gain. It has about 6-7dB gain over a dipole at the same height, but the ground gain makes it 15dB over an isotropic source (which by definition must be in freespace).
While it is true that a higher antenna has less dependence on a good ground, the reason is because field density is less. There is a larger cross-section of dirt involved in the reflection so there is less loss.
We always want good ground, although it is more important when the antenna is close to earth in terms of the wavelength.
If I measure an 80 meter dipole at .1 wavelengths high (25-30 feet) over my soil and add a series of counterpoise or ground screen wires below the antenna, the signal level at ALL distances and angles increases about 5-6 dB from reduced ground loss. The worse the soil, the worse the signal at ALL angles and distances.
The second bad idea is that the BB's would form a reflector. They can't, they are far too small. They might short circuit half of the earth if you have 50% coverage, but that would only double conductivity. One single long wire below the antenna would make dozens of times more improvement than 50% coverage with BB's.
We want good ground below any antenna if possible, but it is much more important with a low antenna. It isn't "unimportant" until we have a horizontal antenna a half wave or higher above ground, and we never want crummy ground. Crummy lossy soil does NOT make an antenna look higher, unless it is something like frozen earth (permafrost) or ice. At the North Pole we could lay our antennas right on the ice, but not in the lower 48.
73 Tom
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RE: An Idea to Improve Ground Conductivity
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by W4VR on July 28, 2007
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I saw Brigette Bardot recently on TV. My 12 year old dog is better looking.
The performance of any antenna, whether vertically or horizontally polarized, is affected by the conductivity of the earth beneath it. Many hams associate ground losses only with vertical antennas. I've always put up horizontal dipoles as opposed to inverted V's...getting those ends too close to ground is not good for overall efficiency.
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RE: An Idea to Improve Ground Conductivity
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by KB5DPE on July 28, 2007
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"nothing like a good dose of copper ions to kill the plants"
That's the first thing I thought of as well; but, that's not all bad as another poster noted. Don't have to mow the lawn, more time on the radio!
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RE: An Idea to Improve Ground Conductivity
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by KC8VWM on July 28, 2007
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I find it ironic that many antenna manufacturers always seem to focus on antenna gain, while many hams always seem to focus on antenna loss. :)
Charles - KC8VWM
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An Idea to Improve Ground Conductivity
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by K1DA on July 29, 2007
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THe 1 micron or so of copper on those things lasts about a day outside. I agree with the thousands of diode junctions theory.
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An Idea to Improve Ground Conductivity
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by K5YEF on July 29, 2007
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Sounds worth a try. What we need is someone to come up with a hybrid grass that is 80% iron and looks like a putting green when cut. OK, I'll roll over and go back to sleep...
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RE: An Idea to Improve Ground Conductivity
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by W6TH on July 29, 2007
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.
Tom W8JI, do you remember this post of yours?
RE: A Vertical Antenna Advantage
by W8JI on May 18, 2005 Mail this to a friend!
Now please Tom show me some knowledge of how you determine the gain of a 5/8 wl vertical over a 1/4 wl vertical.>>>
Vito, I don't use math. It can't possibly work to use math because the effects of earth are much too complex. Even modeling programs have difficulty with earth effects.
I measure it directly. That's part of what I'm paid to do.
You may use 15 degrees for the vertical beamwidth of the 5/8 wl.>>
I don't know what that means. Are you talking about the power contained in that area? We couldn't possibly calculate that without doing FS measurements.
You may use 45 degrees for the vertical beamwidth of the 1/4 wl.>>
? What does that mean??
If you are talking about power density, why would you do it over a 45 degree beamwidth with one antenna and do the other at 15 degrees? That makes no sense at all Vito.
FS comparisons are normally made at a specific angle, not an integration of a wide range of angles.
Or are you talking about the FS at a specific angle? If so, you'd have to pick the same point for both antennas. You wouldn't want to measure one at 45 and the other at 15.
I'm not sure I follow what you are saying.
By the way Vito, AM broadcast stations dropped 5/8th wave antennas like a hot rock after they started using them. The reason for that is they don't actually produce useful gain in fringe areas. They actually have more fading.
The only place we find 5/8th wave antennas in common use is amateur radio and CB radio. That's because the marketing hype keeps deluding people into thinking a 5/8th wave without a very large (several wavelengths) well-conducting groundplane has useful gain.
Of course they would do quite well over saltwater, having almost 3dB over a 1/4 wl tall vertical antenna.
73 Tom
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RE: An Idea to Improve Ground Conductivity
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by K3EY on July 29, 2007
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I remember reading an extensive engineering article about this subject in a club newsletter, not about BB’s but grounding systems and the ground itself.
Every piece of property is different having diverse inherent electrical properties. These all have to be taken into account and worked with accordingly. You can actually measure resistance of earth and with the proper instruments and measurements go from there.
Simply sprinkling down BB"s and choking the birds is a good idea for the birds.
In today’s PC world choking birds will get you time, not DX.
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RE: An Idea to Improve Ground Conductivity
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by W5GNB on July 29, 2007
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I prefer to use the BB's in the proper way, Load your old Daisy Pumper and BLAST all those NASTY birds that CRAP on our antennas!
That sould be at least more effective than throwing them on the ground.........
73's
Gary - W5GNB
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RE: An Idea to Improve Ground Conductivity
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by KG6WOU on July 29, 2007
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An interesting idea, and if it works, it will make AM broadcast stations much less expensive to build.
I have to admit that I'm going with the majority when I say there must be a better way.
If I had known then what I know now, I would have done much more work on grounding when my yard was redone a few years back, I would have sprung for stainless steel or copper mesh to go under the grass, and would have used the other holes to put in deeper ground rods. Sigh.
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RE: An Idea to Improve Ground Conductivity
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by KI0KY on July 29, 2007
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NVIS is generally not applicable to frequencies above 10 MHz.
KI0KY
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An Idea to Improve Ground Conductivity
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by AF6AY on July 29, 2007
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Here's a thought for the Serious ground conductor modifier:
Measure your total lawn area. Find a wholesale dealer of heavy-duty aluminum foil. Buy enough foil to double-cover the measured square area. Then dig up your lawn to pieces of turf convenient to carry. Make it about 3 to 4 inches down. Pile them to one side.
Lay in the foil. Close to an antenna, try for double-layering (maybe triple) as extra insurance and for RF currents that would be higher there. Once laid in, devise a way to get the foil pieces connected electrically and last without corroding. Then return the sod pieces piled to one side. Water sod piles and replanted pieces as needed for your temperature.
There, classic continuous ground plane! Easier than getting thin 6061 aluminum sheet with rivets connecting all of it! Well, you could omit the sod and have the aluminum conductively-film treated and dyed green. A bit costly. Sure would discourage pocket gophers, though. :-)
...or just use a lot of radials like everyone else.
Regards, Len AF6AY
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RE: An Idea to Improve Ground Conductivity
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by KE3WD on July 29, 2007
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Liquid Nitrogen.
Lots of Liquid Nitrogen.
Turn your lawn turf into a superconductor.
.
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An Idea to Improve Ground Conductivity
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by KE4ZHN on July 29, 2007
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How many times a year is it April 1st? Wire radials I can understand. But BB's? Perhaps if you bought 40-50 dump truck loads and made your yard ankle deep in them it may work. Till the EPA busted you for an environmental hazard or your wife shot you anyway. lol
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An Idea to Improve Ground Conductivity
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by KE7GNU on July 29, 2007
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Worked at a radar site high atop a granite mountain. After many complaints from Air Traffic Control about missed traffic, experts were flown in from MITRE to check out the situation.
A few weeks of measurements, tests, and per diem, a very large ( 10' X 10' X 10') hole was dug next to the radar tower and a 10'x 10' sheet of copper was dropped in the hole after bolting it to a 2" dia. copper cable which was ,in turn, bolted to the metal frame of the tower.
The plate was then covered with about 3 feet of copper sulfate, watered down, and then topped off with gravel.
End result was no improvement in the radar reception but MITRE certainly made a few bucks off of the whole fiasco, which was provided by you, the taxpayer, through the USAF.
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RE: An Idea to Improve Ground Conductivity
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by W6EM on July 29, 2007
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..."a 10'x 10' sheet of copper was dropped in the hole after bolting it to a 2" dia. copper cable which was ,in turn, bolted to the metal frame of the tower.
The plate was then covered with about 3 feet of copper sulfate, watered down, and then topped off with gravel."
How long ago was this done? Is the tower still standing?
Just curious as I would suspect that if the tower legs were mild steel and not heavily coated to insulate them from contact with concrete footings and earth, that they've corroded away substantially.
Iron/steel is quite a sacrificial anode to copper. A close to home example is the installation of an isolating/insulating union where galvanized pipe interconnects with copper tubing. (Hint, if your home plumbing is copper and you don't use one on your water heater, you'll have a geyser in your garage in no time).
The AF was very foolish to have bought that solution without thoroughly investigating the effects of a copper cathode electrically bonded to structural steel/iron close by.
I sure wouldn't climb that tower.....
73,
Lee
W6EM/4
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RE: An Idea to Improve Ground Conductivity
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by K8MHZ on July 29, 2007
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"I heard about a couple of old boys were frog gigging and there head lights stoped working they checked the fuse one was bad but they did not have a replacement so they used an unfired twenty two bullet,take a wild guess on what happened."
They discovered that the fuse box was shot?
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RE: An Idea to Improve Ground Conductivity
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by KE5FRF on July 29, 2007
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VK2GWK asked "What's a BB?"
And several followed up saying "little round steel balls" or "things we shot out of an air gun when we were kids"
But I'm surprised nobody told him what BBs actually are.
BB is short for ball bearing. If you bust open a pressed bearing on a motor shaft or most anything that rotates on an axial plane, you will find small greased metallic balls. While BBs that are purchased for the purpose of shooting from a pellet gun may not be real bearings, their name was derived from them.
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An Idea to Improve Ground Conductivity
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by N4VNZ on July 29, 2007
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Standard BB shot measures .177 inch in diameter, more or less (17 caliber).
BB's can be made from lead, also, but are much harder to find than common copper-plated steel BB's. Lead BB's are much more accurate for target shooting.
BB shotgun pellets have shot that approximates the size of a "BB".
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An Idea to Improve Ground Conductivity
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by AI2IA on July 29, 2007
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Forget about improving ground conductivity. Concentrate on installing more of the proper length radials, and you will have a good vertical antenna. I have among others, a twenty meter vertical and a twenty meter dipole. The vertical is superior in all respects. Check your antennas frequently. Prevent or treat corrosion. They are outdoors 24/7, and they will serve you well if you give them reasonable care.
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RE: An Idea to Improve Ground Conductivity
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by N5YPJ on July 29, 2007
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Me thinks that me now may have heard it all.
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An Idea to Improve Ground Conductivity
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by KM6CZ on July 29, 2007
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Copper can be toxic and could contaminate groundwater if accumulated over time.
If you wanted to try a more simple method; try spraying iron sulfate onto the area beneath the antenna. This could temporarily improve ground conductivity although I doubt you will notice any improvement.
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RE: An Idea to Improve Ground Conductivity
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by KC8VWM on July 29, 2007
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Ground conductivity is often improved by saturating the surrounding soil with NaCl. It exhibits excellent solubility in water (35.9 g/100 ml @ 25 °C)and is relatively inexpensive and commonly available when compared to BB's. Many cell phone tower sites and other commercial interests have been known to chemically enhance ground conductivity in this manner.
A little topsoil and grass seed will restore the lawn after treatment. :)
73 de Charles - KC8VWM
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An Idea to Improve Ground Conductivity
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by N0AH on July 29, 2007
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MFJ has been selling the BB radial kit in EU for years- Mostly eastern EU but also regions in the SE USA and rural parts of VK. In other words, they are spreading them around. And try to find one to return- Perfect martin.....................
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RE: An Idea to Improve Ground Conductivity
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by KC8VWM on July 29, 2007
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Another quick and easy way to make radials for vertical antenna's is using a pizza cutter and bury a few flat antenna rotor cables of the 5 wire variety.
73 de Charles - KC8VWM
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RE: An Idea to Improve Ground Conductivity
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by W9WHE-II on July 30, 2007
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Ground radials function by "conducting" a "return" current back to the base of your antenna. The ground is the other half of the dipole. That's why ground wires are used in a "radial" format. "BBs" just won't be the same, because there is no continious path. HOWEVER, spreading salt would increase ground conductivity, as it would increase the conductivity of the soil. There are also a number of commercial earth "treatments" available.
But why?
The amount of signal improvement when you are using a ballanced antenna like a dipole is not worth the effort. The dipole already has the other "half" of the antenna.
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An Idea to Improve Ground Conductivity
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by KG6OMK on July 30, 2007
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How many BBs would it take? Try this simple experiment. Get a small box of dirt. Measure the resistance from one end to the other with an good ohm meter then add BBs until you see the meter move.
I suspect you will need to almost completely cover the surface with BBs. But you can do the experimet and find out. I think you'd need a couple dump truck loads of BBs. Wire would be a lot cheaper.
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An Idea to Improve Ground Conductivity
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by N5XM on July 30, 2007
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At least we have a little candlepower going between neurons here. I love creative thinking of any kind, and so what if the idea really isn't technically up to speed? At least we find another soul who loves radio enough and is honest enough to ask an interesting question. To those of you who might think a question like this is ridiculous, don't take yourselves so seriously. Any lack of experience here is more than made up by enthusiasm.
I wonder if 25 years of premium dog poop randomly placed around my tower and vees has helped the conductivity (the pH for sure!) of my yard?
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RE: An Idea to Improve Ground Conductivity
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by KD0XX on July 30, 2007
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I also like the creative side of thinking.
One problem I could give for spreding the BB's is
if you ever decide to metal detect the yard, you will have a REAL problem:-)
RoD
KD0XX
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An Idea to Improve Ground Conductivity
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by KJ7V on July 31, 2007
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Might want to check with your county agent first. I know that driving copper nails into a tree will kill it. BB's in the yard may do the same to your grass.
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RE: An Idea to Improve Ground Conductivity
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by AA4PB on July 31, 2007
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Can you imagine what someone will think 200 years from now when they use a metal detector on your yard? What kind of battle went on here? :-)
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RE: An Idea to Improve Ground Conductivity
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by W4LGH on August 1, 2007
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Hairbrained to say the least! I understand where you were going with the BB idea, but its a waste of time and good BB's!
Now if you want to dig up your entire yard and place copper screen wire down, then sod over it, you might gain a little something, but again is it worth the cost? Most likely not.
Just string up a wire and play radio. One day someone will come up with a completely new and improved antenna, nothing like ever seen before. Until then we have to work with what we have.
73 de W4LGH - Alan
www.w4lgh.com
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RE: An Idea to Improve Ground Conductivity
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by K4JF on August 1, 2007
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Uh, guys! It's hare-brained (as in compared to the mental capacity of a rabbit), not hair-brained (which has no reference I can find).
:o)
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RE: An Idea to Improve Ground Conductivity
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by K8GWW on August 1, 2007
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Let's talk about counterpoises, this is different than ground conductivity. My 80 meter dipole feedpoint is at 33 feet and I have a wire counterpoinse (1/2 wl plus 5%) one eigth wl under it.
I first saw this in a military antenna book from the 40s and it has been in most of ARRLs antenna books and on the Cebik website. This makes my dipole a two element beam firing straight up. I usually have one of the best signals in any group that I talk to within 600-800 miles. I live in a very sany area.
73, Jerry K8gww <
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RE: An Idea to Improve Ground Conductivity
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by KC8VWM on August 1, 2007
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Are we are just splitting hares on the subject?
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RE: An Idea to Improve Ground Conductivity
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by KB1EYH on August 1, 2007
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Ralphy you could put some one's eye out with that thing . The movie " Red Rider " comes to mind ! I think wire would be my choice ! You might consider the leg lamp :}
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An Idea to Improve Ground Conductivity
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by WB4TGT on August 2, 2007
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might work out ok. i planted 400 ft of number 8 wire 46 inches deep under my antenna. now some one will say i talk under ground
well thats what its about. kep thinking. i got lots spreaders if anyone needs one
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RE: An Idea to Improve Ground Conductivity
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by AC5WA on August 3, 2007
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Spend your money on chicken wire. The zinc plated steel mesh will increase the conductivity much more effectively than several times the cost of BB shot of what ever description.
73 de AC5WA
Gerald
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RE: An Idea to Improve Ground Conductivity
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by KT8K on August 7, 2007
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I drove the ground rod closest to my station about a foot from the sump pump outlet. I think that will keep the soil damp, and improve the quality (lower the resistance) of my ground system, automatically.
In any case, radial wires are certainly a lot better alternative than BBs. Clever idea, though. Keep thinkin', folks.
73 de kt8k - Tim
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An Idea to Improve Ground Conductivity
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by KI6FCI on August 7, 2007
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So I'm not the only one who has thought of this idea! Didn't really think it would work.
It's amazing what a creative mind comes up with 500 miles into a 650 mile shift at 0300. ;) Remember, every once in a while someboby's crazy idea actually works.
How's this for an idea: Till up your yard real good, install a nice automaticly controlled sprinkler system, and right before the truck shows up to deliver your new sod lay down chicken wire over the whole yard. The grass root system wouldn't even notice the chicken wire & water would pass right through. It would look like a solid sheet of metal to RF.
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RE: An Idea to Improve Ground Conductivity
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by K1CJS on August 8, 2007
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"What we need is someone to come up with a hybrid grass that is 80% iron and looks like a putting green when cut."
Here is a better one--how about a plant tough as one of those pesky weed-vines that are next to impossible to cut or clear away, and grow in the shape of a tower! Since I'm dreaming, I'll just get back to the bands instead of going back to sleep.
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RE: An Idea to Improve Ground Conductivity
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by WD9ICU on August 8, 2007
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The first thing you need to do is bulldoze your property flat and remove all obstructions.The next most important step is to completly cover your property with copper sheeting.Your xyl will thank you when it turns green, and you can sell the lawn mower and buy more radio goodies
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RE: An Idea to Improve Ground Conductivity
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by KC0YEF on August 9, 2007
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put enough shot down and you can run a NVIS just lower the pitch of the inverted V to 110 degrees
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RE: An Idea to Improve Ground Conductivity
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by KL7AJ on August 10, 2007
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Back in the dark ages some of us broadcasters used copper chloride and charcoal to try to improve the ground conductivity around our antennas. Yikes...could you imagine what the EPA would think of that now!
I don't think any of that actually worked. At least at medium wave frequencies, the ground conductivity FAR away from your "jurisdiction" can have as much effect on overall performance as that right under your antenna. It gave us a warm fuzzy feeling that we were doing something useful anyway. But since, for all practical purposes, we had a perfect ground anyway....120 buried 1/4 wave radials.
Here's something I always recommend...a good R.F. ammeter. Anything you do that increases the current in your vertical radiator is good. (Assuming your true radiation resistance is unchanged) If you don't see a significant change with whatever you do to your ground system....well, it isn't helping too much.
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RE: An Idea to Improve Ground Conductivity
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by KB3MRU on August 14, 2007
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I think the copper/steel pellets would degrade too fast in the soil. You would do better using solid gold coins... perhaps a couple thousand 1oz. Maple Leafs.
Cheers,
Mark
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