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Ground system hint requested by a customer...

C

carlvanorden

Guest
Seems that customers think they need to dig up their back yard to bury their ground radials....not so!......
I simply use a hand tool called an ice chopper (looks like a hoe but the blade is straight), or you could use a flat blade shovel.........>>>>>>>>>
The ice chopper works great: I simply inserted the chopper into the sod, pressed it with my foot (as the blade is about 6" tall), moved it back and forth, removed it and went on to the next section...the blade also is about 6 inches long.....continue to make slices into your sod until you have gone the amount of feet of your radial........insert your radial and use the same tool to press it down into the trench, then press the sod down with your foot.......very simple and easy installation for your ground system.
Carl<P ID="signature">______________
[email protected], [email protected],[email protected]</P>
 
> Seems that customers think they need to dig up their back
> yard to bury their ground radials....not so!......
> I simply use a hand tool called an ice chopper (looks like a
> hoe but the blade is straight), or you could use a flat
> blade shovel.........>>>>>>>>>
> The ice chopper works great: I simply inserted the chopper
> into the sod, pressed it with my foot (as the blade is about
> 6" tall), moved it back and forth, removed it and went on to
> the next section...the blade also is about 6 inches
> long.....continue to make slices into your sod until you
> have gone the amount of feet of your radial........insert
> your radial and use the same tool to press it down into the
> trench, then press the sod down with your foot.......very
> simple and easy installation for your ground system.
> Carl
>


Carl,

For your antenna buyers or anyone thinking of installing a vast radial system..

I used an electric edger and ran the radial lines in diameter segments then slightly seperated the soil/grass with a small shovel and simply placed the wires about 2-3 inches in the ground covered with potting mix... but I've been reading that cat litter is extremely better as the clays in the cat litter is much better conductively than soil. Also the ground rod is conductively better if it is laid down with a 2-3 inch diameter bed of clay or cat litter clay... this stuff is very cheap to use... as the clays bind it traps moisture in and keeps the conductivity of the soil longer... those in dry areas may want to use this method, I'm in a wet salty area so the conductivity is always very high, around 20-30 mho's or better!

Radiopilot
 
An EXCELLENT idea to compliment mine!

> > Seems that customers think they need to dig up their back> > yard to bury their ground radials....not so!......> > I simply use a hand tool called an ice chopper (looks like> a> > hoe but the blade is straight), or you could use a flat> > blade shovel.........>>>>>>>>>> > The ice chopper works great: I simply inserted the> chopper> > into the sod, pressed it with my foot (as the blade is> about> > 6" tall), moved it back and forth, removed it and went on> to> > the next section...the blade also is about 6 inches> > long.....continue to make slices into your sod until you> > have gone the amount of feet of your radial........insert> > your radial and use the same tool to press it down into> the> > trench, then press the sod down with your foot.......very> > simple and easy installation for your ground system.> > Carl> > > > > Carl,> > For your antenna buyers or anyone thinking of installing a> vast radial system.. > > I used an electric edger and ran the radial lines in> diameter segments then slightly seperated the soil/grass> with a small shovel and simply placed the wires about 2-3> inches in the ground covered with potting mix... but I've> been reading that cat litter is extremely better as the> clays in the cat litter is much better conductively than> soil. Also the ground rod is conductively better if it is> laid down with a 2-3 inch diameter bed of clay or cat litter> clay... this stuff is very cheap to use... as the clays bind> it traps moisture in and keeps the conductivity of the soil> longer... those in dry areas may want to use this method,> I'm in a wet salty area so the conductivity is always very> high, around 20-30 mho's or better!> > Radiopilot> Most customers don't understand that wet soil compliments AM antenna systems!.....therefore, something that will absorb moisture (albeit temporary) will help to elongate the part 15 am signal. Another thing that may be more stable is solid insulation.....it comes in pellets and I've forgotten it's name, but you can buy it in bags at homecenters.....this stuff is so absorbant (it is often poured into spaces between rafters in attics)...(vermiculite?) that it often becomes too heavy when there is a fire and it absorbs water immediately. This is also good in a garden.I did not mention a tiller cause I feel people can't afford one, so I spelled out my very easy method of installing a ground system; but your way is excellent as well. Thanks for contributing!!......over and out.Carl<P ID="signature">______________
[email protected], [email protected],[email protected]</P>
 
Re: An EXCELLENT idea to compliment mine!

Aren't 8 foot copper clad ground rods supposed to be attached to the far end of each ground radial? Any ideas as to how this can be accomplished without having a heart attack????
 
Re: An EXCELLENT idea to compliment mine!

> Aren't 8 foot copper clad ground rods supposed to be
> attached to the far end of each ground radial? Any ideas as
> to how this can be accomplished without having a heart
> attack????
>


The answer would be no....

The radials just end, think of it as a spoke wheel... The more the better, the idea is to bring the resistance to below 1 ohm or less... 120 radials of 1/4 wavelength is the true ideal, but 64 will give you the best performance. I my self have 64 - 75 foot radials and the resistance is very low, almost unmeasurerable... use 12 gauge or less pure copper wire, Home Deopt sells 500 foot rolls of 12 gauge insulated wire for $26, you'll have to scrape the insulation off before using, I used an x-acto blade with the wire stretched and was able to strip 75' in one continous run.

All the radials should end in a small circle and soldered to a ground rod or rods 8 feet or longer in the center of the radials... that's it... other than the above suggestions for installing the radials, you should see almost double the range and signal strength.

Good luck.

Radiopilot
 
Ground radials number vs. length

Also, our buried ground radials need not be longer than the antenna is tall, since a shortened, loaded vertical antenna has a more compact near field. A 6 meter wide shallow-buried square or circle of copper sheet (or 120 three-meter long buried bare copper wires) work better than fewer longer radials.

Buried ground radials don't have to be resonant. As this University of Hawaii Ham Radio web page http://www.chem.hawaii.edu/uham/radials.html explains:

"Ground radials need not be resonant...Ground radials do not need to be much longer than the antenna is tall. A shortened antenna with loading coils will have a more compact "near field" where the majority of the antenna field is. The ground needs only reach out as far as the near field extends. Field intensity drops off with the square of the distance from the base of the antenna...The ground around a vertical monopole type antenna can be viewed as strings of series connected resistors fanning out from the base. The purpose of the radials can be viewed as attempting to short circuit as many of these resistors near the base as possible. This is especially critical very close to the base where RF field density is highest, and its importance drops off quickly beyond 1/8th wavelength from the base of any vertical antenna, where the RF field density per unit area goes down sharply."

"It is important not to confuse this application with elevated ground planes. We are talking about radials that supplement the return of ground currents to the base of the antenna, especially in the near field. They work "in parallel" with the existing earth ground surface to supplement it. Elevated radials are a resonant element and serve a decoupling function and establish a completely artificial ground. They should be resonant, quarter wave wires, but still in fair numbers, probably more than the four usually seen, for best results."

The web page also describes interesting portable set-ups (which could be used for Part 15 AM remote broadcasts) in which they use large metal gluing clamps to connect ground leads to fire hydrants, irrigation pipes, backflow preventers, and large water mains ("These masses of metal act as giant counterpoises as well as being metalic paths for ground currents to supplement soil conductivity. Plus since they are buried in the ground, they have good ground contact over a very large surface area for many wavelengths.") -- Jason
 
Re: Ground radials number vs. length

Jason,

Please submit a copy of this explanation of proper grounding for short verticles to part15.us.

I hate to see this dissapear into the oblivion of the board.

Thanks,

Rev. Robert P. Chrysafis<P ID="signature">______________
Rev. Robert P. Chrysafis
Universal Life Ministries (ULC)

http://www.freecycle.org
Join the FreeCycle Revolution</P>
 
Re: An EXCELLENT idea to compliment mine!

> Home Deopt sells 500 foot rolls of 12 gauge
> insulated wire for $26, you'll have to scrape the insulation
> off before using, I used an x-acto blade with the wire
> stretched and was able to strip 75' in one continous run.
>

Our local Home Depot sells 100 and 500 ft roles of bare copper wire in sizes #14, #12 and #10. Electrical supply stores also sell bare copper wire. Its used for ground (along with the insulated wires for hot and neutral) to pull through plastic conduit. You don't have to strip it and it's cheaper.
<P ID="signature">______________
Phil B
</P>
 
Re: Ground radials number vs. length

> Jason,
>
> Please submit a copy of this explanation of proper grounding
> for short verticles to part15.us.
>
> I hate to see this dissapear into the oblivion of the board.
>
>
> Thanks,
>
> Rev. Robert P. Chrysafis
>

I just posted on a similar thread on part15.us. I quoted Jason's post and asked Rich, the resident antenna and ground guru there, for his comments.<P ID="signature">______________
Phil B
</P>
 
> Carl,
>
> For your antenna buyers or anyone thinking of installing a
> vast radial system..
>
> I used an electric edger and ran the radial lines in
> diameter segments then slightly seperated the soil/grass
> with a small shovel and simply placed the wires about 2-3
> inches in the ground covered with potting mix... but I've
> been reading that cat litter is extremely better as the
> clays in the cat litter is much better conductively than
> soil. Also the ground rod is conductively better if it is
> laid down with a 2-3 inch diameter bed of clay or cat litter
> clay... this stuff is very cheap to use... as the clays bind
> it traps moisture in and keeps the conductivity of the soil
> longer... those in dry areas may want to use this method,
> I'm in a wet salty area so the conductivity is always very
> high, around 20-30 mho's or better!
>
> Radiopilot


Also, as an alternative, you can rent a "wire trencher" machine at any rental store. The most common use for these is for burying an "invisible fence" radio dog fence wire aroung the perimeter of your property. These things cut a groove in the ground about 1/2" wide and about 3 or 4 inches deep. They run about as fast as you can comfortably walk. Then just push the wire down to the bottom of the groove and walk over the groove to close it a little. The groove will close by itself after a rain.

If anyone really wants to get serious, I watched the Phone company guys bury a phone cable about 3 ft deep with a BIG wire trencher. You might be able to rent one of those, but it sure would have to be a lot more expensive than a dog fence trencher!

Of couse, the little groove these things cut won't allow you to add kitty litter. There's a joke in here somewhaere about kitty litter and dog fences, but I won't go there!

<P ID="signature">______________
Phil B
</P>
 
Re: Ground radials number vs. length

> Also, our buried ground radials need not be longer than the
> antenna is tall, since a shortened, loaded vertical antenna
> has a more compact near field. A 6 meter wide
> shallow-buried square or circle of copper sheet (or 120
> three-meter long buried bare copper wires) work better than
> fewer longer radials.
>
> Buried ground radials don't have to be resonant. As this
> University of Hawaii Ham Radio web page
> http://www.chem.hawaii.edu/uham/radials.html explains:
>
> "Ground radials need not be resonant...Ground radials do not
> need to be much longer than the antenna is tall. A
> shortened antenna with loading coils will have a more
> compact "near field" where the majority of the antenna field
> is. The ground needs only reach out as far as the near
> field extends. Field intensity drops off with the square of
> the distance from the base of the antenna...The ground
> around a vertical monopole type antenna can be viewed as
> strings of series connected resistors fanning out from the
> base. The purpose of the radials can be viewed as
> attempting to short circuit as many of these resistors near
> the base as possible. This is especially critical very
> close to the base where RF field density is highest, and its
> importance drops off quickly beyond 1/8th wavelength from
> the base of any vertical antenna, where the RF field density
> per unit area goes down sharply."
>
> "It is important not to confuse this application with
> elevated ground planes. We are talking about radials that
> supplement the return of ground currents to the base of the
> antenna, especially in the near field. They work "in
> parallel" with the existing earth ground surface to
> supplement it. Elevated radials are a resonant element and
> serve a decoupling function and establish a completely
> artificial ground. They should be resonant, quarter wave
> wires, but still in fair numbers, probably more than the
> four usually seen, for best results."
>
> The web page also describes interesting portable set-ups
> (which could be used for Part 15 AM remote broadcasts) in
> which they use large metal gluing clamps to connect ground
> leads to fire hydrants, irrigation pipes, backflow
> preventers, and large water mains ("These masses of metal
> act as giant counterpoises as well as being metalic paths
> for ground currents to supplement soil conductivity. Plus
> since they are buried in the ground, they have good ground
> contact over a very large surface area for many
> wavelengths.") -- Jason
>


JasonW,

I can assure you that I had 20 foot radials and only got 2 miles of range from the transmitter with 16 radials, then I added to the length of the radials by 50 feet+ and install a total of 64 radials as stated earlier and it was a dramatic improvement! Don't know how many have followed the same results, but the range increase to 5 miles and I'm sure that if the radials were longer say 100 feet and or the amount of radials increased to 120 or so, the range should almost go out to 7-8 miles during the day.

You can read as many literature is out there or input whatever information into computer models but the end result is field experimentation and seeing first hand results as everyones 'system' will not be the same, as ground conductivity is different for everyone, antenna, and transmitter efficency, etc.

I've read the above website many times about the best grounds, etc.. and yes a pipe system complex is the best ground, but how many of us have fire hydrants in the middle of our backyards? Running a long wire on the ground from the transmitter to a pipe located 30 feet away or longer negates the ground for the transmitter and you may as well just run it to a ground rod simply place next to the transmitter.

A better conductor than round copper wire is flat copper 1 inch strap, but this is hard to obtain, plus it's costly, a wire mesh 'chicken wire' is good around the center of the radials about 10-15 diameter soldered directly to the radials will be a big improvement also.

Radiopilot
 
Re: Ground radials number vs. length

My ground consists of a 1'1/2 copper pipe in form of a ring 4ft in diameter then drilled 120 holes for the radials, I currently have 40 radials ranging from 20ft to 227ft 8, 6 and 12 guage wire my goal is have 120 radials. these radial are silver soldered to the copper ring.

the ring is then connected to the crank up mono pole with 00 guage wire, I have rock salt, cat litter and fertilizer 10ft in diameter from the center "burried".

and yes I get out!!! plus every radial I add, I notice the signal change and the patern also changes.

Maurice



> > Jason,
> >
> > Please submit a copy of this explanation of proper
> grounding
> > for short verticles to part15.us.
> >
> > I hate to see this dissapear into the oblivion of the
> board.
> >
> >
> > Thanks,
> >
> > Rev. Robert P. Chrysafis
> >
>
> I just posted on a similar thread on part15.us. I quoted
> Jason's post and asked Rich, the resident antenna and ground
> guru there, for his comments.
>
 
Re: Ground radials number vs. length

> My ground consists of a 1'1/2 copper pipe in form of a ring
> 4ft in diameter then drilled 120 holes for the radials, I
> currently have 40 radials ranging from 20ft to 227ft 8, 6
> and 12 guage wire my goal is have 120 radials. these radial
> are silver soldered to the copper ring.
>
> the ring is then connected to the crank up mono pole with 00
> guage wire, I have rock salt, cat litter and fertilizer 10ft
> in diameter from the center "burried".
>
> and yes I get out!!! plus every radial I add, I notice the
> signal change and the patern also changes.
>
> Maurice
>

I noticed you have radials of a different length. I'm thinking if I set up an LPAM P15 I'd have to do that because of the way my yard is (rectangular, some above and underground obstructions, on a hill, etc. (btw it would be set up over a septic leech line system.)
What do you notice about your pattern changes with your radials? I'd like to mostly throw my signal in an arc from due west to due north, with not as much in other directions. Does the signal get stronger if you use longer / more radials in the direction that you put those radials? If that's the case, I should put my TX at the southeast portion of the property (although uphill is north).

Also, I notice you guys say you get somewhere around 5 miles with your setups, and might expect 8 if it was better (and had gotten 1 or 2 when your ground was simple). When you say your signal goes that far, is it there that it's getting lost in the background static on a good car radio or portable radio with a large loop antenna, OR, is it where you have a completely static free signal on a cheap portable radio even right next to a computer with several defective flourescent lights in the room and some dimmer switches (I'd add other static-producing things, but I can't think of what ones are common - I'm trying to think of ones that are at least 20 to 30dB stronger than the ones I've mentioned), OR is it somewhere in between?
Where I am, ground conductivity is somewhere around 8-15. In my back yard I am estimating I might have about 124 feet wide (east/west) by 58 feet high (north/south). Somewhere in the middle is a small tree, at the south end is a small 10x16' building (both are within the area that I specified for my ground system). Fences and things block off access to more places to put ground radials.
I was wondering approximately how far on a good portable radio (like a Sony SRF-42) with one of Bruce Carter's loop antennas, would a properly set up part 15 AM signal be heard, until it's about 3dB above the noise floor (assuming a suburban / semi-rural receiving location)?
 
Re: Ground radials number vs. length

First thought there is no Need to strip the insulation Off the #12 wire Before you bury it
Second thought... you dont need 64 radials or 120 radials
you could just Run 4 radials at a height of 8-10 feet above ground if possible
and that would work Just fine. Several Commercial stations using Unipoles are doing just that. 4-8 radials 8-10 feet above the ground. with killer signals..
 
Re: An EXCELLENT idea to compliment mine!

> > Aren't 8 foot copper clad ground rods supposed to be> > attached to the far end of each ground radial? Any ideas> as> > to how this can be accomplished without having a heart> > attack????> > > > > The answer would be no.... > > The radials just end, think of it as a spoke wheel... The> more the better, the idea is to bring the resistance to> below 1 ohm or less... 120 radials of 1/4 wavelength is the> true ideal, but 64 will give you the best performance. I my> self have 64 - 75 foot radials and the resistance is very> low, almost unmeasurerable... use 12 gauge or less pure> copper wire, Home Deopt sells 500 foot rolls of 12 gauge> insulated wire for $26, you'll have to scrape the insulation> off before using, I used an x-acto blade with the wire> stretched and was able to strip 75' in one continous run. > > All the radials should end in a small circle and soldered to> a ground rod or rods 8 feet or longer in the center of the> radials... that's it... other than the above suggestions for> installing the radials, you should see almost double the> range and signal strength.> > Good luck.> > Radiopilot> Like the radio boards, this one also seems to attract not only the people that know the most about part 15, but also the people that do things exactly right........I build a few different ground systems, and in no way are they 75 feet long.....reason is simple: about 90% of my customers are on a very real budget, so I provide about the minimum that they can get by with, of course they can always upgrade. I just don't think there are a lot of people with a part 15 am tx out there with 150 running feet of radial......but, wow.........if you have a sstran, the ground wire goes to the mast pipe and the ground system connects to that mast pipe, giving a pretty solid ground....and like you said, and I always say; your ground is 50% of your signal.....they better you can do it, the better off you will be.>>>>>>..and there is no real good reason to terminate radials with a ground rod......if you need to use a ground rod, so be it but it is no replacement for radials.<P ID="signature">______________
[email protected], [email protected],[email protected]</P>
 
An Excellent Point, Jason.......

> Also, our buried ground radials need not be longer than the> antenna is tall, since a shortened, loaded vertical antenna> has a more compact near field. A 6 meter wide> shallow-buried square or circle of copper sheet (or 120> three-meter long buried bare copper wires) work better than> fewer longer radials.> > Buried ground radials don't have to be resonant. As this> University of Hawaii Ham Radio web page> http://www.chem.hawaii.edu/uham/radials.html explains:> > "Ground radials need not be resonant...Ground radials do not> need to be much longer than the antenna is tall. A> shortened antenna with loading coils will have a more> compact "near field" where the majority of the antenna field> is. The ground needs only reach out as far as the near> field extends. Field intensity drops off with the square of> the distance from the base of the antenna...The ground> around a vertical monopole type antenna can be viewed as> strings of series connected resistors fanning out from the> base. The purpose of the radials can be viewed as> attempting to short circuit as many of these resistors near> the base as possible. This is especially critical very> close to the base where RF field density is highest, and its> importance drops off quickly beyond 1/8th wavelength from> the base of any vertical antenna, where the RF field density> per unit area goes down sharply." > > "It is important not to confuse this application with> elevated ground planes. We are talking about radials that> supplement the return of ground currents to the base of the> antenna, especially in the near field. They work "in> parallel" with the existing earth ground surface to> supplement it. Elevated radials are a resonant element and> serve a decoupling function and establish a completely> artificial ground. They should be resonant, quarter wave> wires, but still in fair numbers, probably more than the> four usually seen, for best results."> > The web page also describes interesting portable set-ups> (which could be used for Part 15 AM remote broadcasts) in> which they use large metal gluing clamps to connect ground> leads to fire hydrants, irrigation pipes, backflow> preventers, and large water mains ("These masses of metal> act as giant counterpoises as well as being metalic paths> for ground currents to supplement soil conductivity. Plus> since they are buried in the ground, they have good ground> contact over a very large surface area for many> wavelengths.") -- Jason> When I first started building ground systems, I looked at the size of the antenna.....9.5 feet. That is the size of my basic radial. Although if the guys building large ground systems feel they benefit from doing so, I say more "power" to them!...Then there is the 1/4 wavelength arguement: the part 15 antenna is so far away from being a 1/4 wavelength that the thinking there, to me is nearly irrelevant.>>>>>>>>>>MOST, but not ALL AM broadcast stations employ a 1/4 wavelength tower or DA....now a days it is because of height restrictions but back in the day, it was because it was cost prohibitive to build something higher.....the ground systems "mirrored" the antenna, by being as long as the tower (in this case, antenna) is tall.....therefore, it was and is my thinking that anything more than 10 feet long for a radial may be a waste of money. Yes, the resistance does lower, but I'm not too sure if the additional range, if any, is worth the cost of the supplies and time to install a large ground system. I'm not saying not to do it; I'm saying that a bare minimum of 10 feet is about all we have proven to be effective in part 15 broadcasting.......but it is turning out to be an interesting discussion!!Carl<P ID="signature">______________
[email protected], [email protected],[email protected]</P>
 
Viberadio... You prove my point!

> My ground consists of a 1'1/2 copper pipe in form of a ring
> 4ft in diameter then drilled 120 holes for the radials, I
> currently have 40 radials ranging from 20ft to 227ft 8, 6
> and 12 guage wire my goal is have 120 radials. these radial
> are silver soldered to the copper ring.
>
> the ring is then connected to the crank up mono pole with 00
> guage wire, I have rock salt, cat litter and fertilizer 10ft
> in diameter from the center "burried".
>
> and yes I get out!!! plus every radial I add, I notice the
> signal change and the patern also changes.
>
> Maurice
>

Maurice,

You have just proven that this system of long radials, (64, 120+) will be the biggest improvement outside of increasing the wattage!

Rich below also proves this as well... Thanks Rich!

Radiopilot
 
Re: Ground radials number vs. length

I believe you are in Miami
Would you be able to build one of these systems for me.
I am willing to pay for your service

thanks

simcha




> My ground consists of a 1'1/2 copper pipe in form of a ring
> 4ft in diameter then drilled 120 holes for the radials, I
> currently have 40 radials ranging from 20ft to 227ft 8, 6
> and 12 guage wire my goal is have 120 radials. these radial
> are silver soldered to the copper ring.
>
> the ring is then connected to the crank up mono pole with 00
> guage wire, I have rock salt, cat litter and fertilizer 10ft
> in diameter from the center "burried".
>
> and yes I get out!!! plus every radial I add, I notice the
> signal change and the patern also changes.
>
> Maurice
>
>
>
> > > Jason,
> > >
> > > Please submit a copy of this explanation of proper
> > grounding
> > > for short verticles to part15.us.
> > >
> > > I hate to see this dissapear into the oblivion of the
> > board.
> > >
> > >
> > > Thanks,
> > >
> > > Rev. Robert P. Chrysafis
> > >
> >
> > I just posted on a similar thread on part15.us. I quoted
> > Jason's post and asked Rich, the resident antenna and
> ground
> > guru there, for his comments.
> >
>
 
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