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Amateur Radio Antennas - For discussion of all amateur band designed antennas and related accoutrements. This includes base, handheld, mobile and repeater usage. For commercial antennas on the amateur bands please use Commercial Radio Antennas below.

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Old 07-16-2017, 5:41 PM
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Arrow First tower/mast. Location and material.

I am looking at putting up my first tower/mast at the house. I was looking at putting up a 50'Rohn antenna at first. What got me started with wanting an external antenna was an offer from a friend for a free 100 foot Rohn. All i had to do was haul it off and install it. Well, knowing that i would have to inspect every weld, have it professionally installed, and then have guy wires running around, i decided against it. So, then i started to look into self supporting antennas.
Long story short, I have free power poles that are 40 foot long laying around the property. I know that i could sink them in 15% (6 feet) leaving me with a 34 foot mast. I know this has been done by many before me. I have a few questions about this and the antenna before i actually start the hole and get things set.

First, I was looking at the Diamond X700HNA Dualband Base/Repeater Antenna for use with my Yaesu FT-8800R. Is this antenna still as highly recommended as it use to be? I was looking for a stationmaster or clone and this is the best quality antenna i could come up with. I will be limited by tower height because i don't want anything that has to be guyed out. So the tower/mast will have a set height above ground.
I have heard some of the argument that if i decide to go higher and instead keep the overall height the same, that i could have a shorter antenna at the same maximum height, but possibly with better coverage because of the antenna emitting in the middle of the mast that would then technically make it taller.
Example:
34' mast + X700HNA @ 24'= 46', with max height at 60'
50' mast + x300A @ 10'= 55', with max height at 60'
Am in understanding correctly that the antenna will radiate the signal from the middle of the antenna?

This is indifferent to my decision on the height because i will be restricted to the height of the actual 40' mast. So for me the antenna should still be sitting at a max of 60' but hopefully without guy lines.

Has anyone else done something similar with this or a similar antenna and if so, did you have to guy it out?
Is there a better antenna for this setup? I would prefer to keep the cost of antenna at $400 or less. I am not interested in making my own right now as i don't want to monkey around with a home-brew antenna when i need to get it this high up in the air. I definitely want to make some of my own and test them out, but will wait until I'm on the air better so i still have something to use while i play and learn.

I can hit all of the local repeaters from home with a 5 watt HT, so this setup is intended to add range for simplex and to get me into the repeaters better. Long range Simplex is the biggest reason for the tower. I know, I know HF... Right now I'm just looking at extending vhf/uhf and I'm not interested in directional antennas. That will come later.

I have been trying to find an Elmer in my area and hope that I have a lead on one. Unfortunately the one that i had been using lately for this stuff isn't as sharp as he use to be. The man is an incredible wealth of knowledge. Unfortunately he is in his late 80's and was in a car accident a while back. He has been focused on getting better and is not the same as he was before his accident. His mind is also starting to slip and Alzheimer's and dementia are setting in. I wish him the best and hope he pulls thru, but as of right now I'm not bugging him with questions like this as he can no longer follow along with the conversation.

I know this is the antenna section, but i don't see a tower section other than on the scanner threads. So if I'm missing something, please let me know.
I plan on paying some guys that set these poles for a living and having them sink it in the ground for me. Like i said, its 40', and has 4 gauge solid copper wire from the top all the way to the bottom. The bottom of the pole has a number of loops at the base (not wrapped around the bottom of the pole, but in circles under the base).

My plan is to sink this in at 6', ground it with a solid 10' grounding rod, tied in with new stainless steel hardware. Have the coax grounded at the pole.
Should i add extra grounding rods?
I thought i might skip the LMR 400 and go with LMR1200. My total run depending on location of the pole will be approximately 65 feet or less. Is this a good idea or a waist of money? I would rather buy once / cry once when it comes to coax and antenna.
LMR-400 LMR-1200
144 mhz (1.5) (0.46)
220 mhz(1.8) (0.56)
450 mhz (2.7) (0.83)

How important or how noticeable would it be for me to switch form LMR-400 to 1200?

Sorry this is kinda random and garbled. I am overwhelming myself quickly with my own questions and unknowns when it comes to an antenna project like this. I know is should be simple, i guess my biggest concern going into this is that i don't want a lightning rod that is going to bring lighting straight into the house.

Last edited by 19dsniper; 07-16-2017 at 7:24 PM..
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Old 07-16-2017, 9:20 PM
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There's a whole lot of variables involved, and too many to try and guess at.

A good condition pole is a great option. The depth it needs to be buried will depend on the amount of wind load, what the soil is like, etc. etc.
If the wind load is low and it's buried deep enough in hard packed soil, guying probably won't be an issue.

I'd talk to the installers and see what they think. They should be able to give you some good info.
As for grounding, it's important, especially if you have a lot of lightning activity in your area, and I'm sure you do. The pole base grounding might not be enough. Usually you'd be looking for a certain amount of resistance between the ground wire and earth. You may or may not need ground rods in addition to the pole base.
It's a good idea to read the National Electric Code section on grounding communications systems. You are right to be concerned, and based off an install like this, you'd be best served by contacting an electrician. There's a lot to it, and it really needs to be done right.

As for the poles, consider you'll need to change or maintain your antennas at some point. Might be a good idea to have the installers install pole steps while they are at it. Either that, or count on renting a lift.

As for coax, it really depends on how long the cable run is.
Signal loss in coaxial cable increases with length, and it increases with frequency.
If your run is really short, LMR-400 might be "good enough". The "good enough" part is something -you- need to decide on.
Going larger than LMR-400 would probably be better done with Heliax type cable. It's got a little less loss compared to similar sized LMR type cables. Heliax and it's connectors are often easier to find and install than the larger LMR type connectors. Also, the foil/braid used on the LMR cables can be problematic if you ever want to run a repeater. Water intrusion and corrosion between the foil and braid becomes a big issue.
For what it's worth, I'm using LMR-600 at home for a base VHF radio. I have lots of it and have the correct stripping and crimping tools, so it's easy to do. It works fine and if it's what you want to use, then go for it.

Sounds like a interesting project.
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Old 07-16-2017, 9:22 PM
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Well, I hate to do it but the system won't let me go back and edit/add information without contacting an administrator for some reason.

I will be using Times Microwave cable for either the LMR-400 or 1200. Or whatever is recommended. Also, seeing how 3db is 1/2 power, i will essentially be looking at a line loss of approximately 2db at a 65' run of LMR-400. That basically only gives me 23 watts out on UHF. Where as if i was to use the LMR-1200, I will be down 0.53 db, giving me 33 watts out. Did i do the math correctly on that one? I think i did.
I won't be using UHF that frequently that i know of. I don't plan on using it for simplex, but may play with it a little and see how it does in our area. I normally use VHF and can already get 26 miles from my driveway from my jeep to my wife's suburban. You never know, I just might be able to reach some of the UHF repeaters in Waco. I finally heard them for the first time last night after setting up a mag mount on top of the shed and using a Baofang UV-5R.
I was able to pick up distant stations last night from my first ham radio (2001 yaesu vx-150) and a mag mount that i couldnt pick up in the house with my FT 8800R and a J-pole in the attic.
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Old 07-16-2017, 9:26 PM
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Quote:
Originally Posted by 19dsniper View Post
I thought i might skip the LMR 400 and go with LMR1200. My total run depending on location of the pole will be approximately 65 feet or less. Is this a good idea or a waist of money? I would rather buy once / cry once when it comes to coax and antenna.
LMR-400 LMR-1200
144 mhz (1.5) (0.46)
220 mhz(1.8) (0.56)
450 mhz (2.7) (0.83)

How important or how noticeable would it be for me to switch form LMR-400 to 1200?
OK, I see where you said "65 feet or less".

On UHF, the almost 2dB difference is pretty big.
I'd look at 1/2 inch Heliax as a good solution. (LDF4-50)
7/8" would be a good step up from there.
Going much larger, like 1 5/8" would be pretty extreme. The thing you need to be concerned about with these larger cables, both heliax and LMR, is that it's gets pretty stiff as you go up in size. Routing that heavy cable into and through your home can be an issue.

It's pretty common for short jumpers of a more flexible cable to be used at either end. Using a jumper to transition between the heavy coax and your antenna, and the same at the radio end, can make life a lot easier and prevent damage to connectors on the radio and antenna.
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Old 07-16-2017, 9:31 PM
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Give this site a try to see what different coax cables will do for you:
Coax Loss Calculator

Getting a good antenna up high and feeding it with good cable will really improve things for you. If you have the budget for it, I think it's going to turn out well.

If you think you may want to try HF at some point, you might want to have them plant another pole or two on your property. Putting them about 300 feet apart with your radio in the middle would allow you to string up a full length 160 meter dipole. Getting them planted why the guys are there might be cheaper than having them come back later.
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Old 07-16-2017, 10:03 PM
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Quote:
Originally Posted by mmckenna View Post
There's a whole lot of variables involved, and too many to try and guess at.

A good condition pole is a great option. The depth it needs to be buried will depend on the amount of wind load, what the soil is like, etc. etc.
If the wind load is low and it's buried deep enough in hard packed soil, guying probably won't be an issue.

I'd talk to the installers and see what they think. They should be able to give you some good info.
As for grounding, it's important, especially if you have a lot of lightning activity in your area, and I'm sure you do. The pole base grounding might not be enough. Usually you'd be looking for a certain amount of resistance between the ground wire and earth. You may or may not need ground rods in addition to the pole base.
It's a good idea to read the National Electric Code section on grounding communications systems. You are right to be concerned, and based off an install like this, you'd be best served by contacting an electrician. There's a lot to it, and it really needs to be done right.

As for the poles, consider you'll need to change or maintain your antennas at some point. Might be a good idea to have the installers install pole steps while they are at it. Either that, or count on renting a lift.

As for coax, it really depends on how long the cable run is.
Signal loss in coaxial cable increases with length, and it increases with frequency.
If your run is really short, LMR-400 might be "good enough". The "good enough" part is something -you- need to decide on.
Going larger than LMR-400 would probably be better done with Heliax type cable. It's got a little less loss compared to similar sized LMR type cables. Heliax and it's connectors are often easier to find and install than the larger LMR type connectors. Also, the foil/braid used on the LMR cables can be problematic if you ever want to run a repeater. Water intrusion and corrosion between the foil and braid becomes a big issue.
For what it's worth, I'm using LMR-600 at home for a base VHF radio. I have lots of it and have the correct stripping and crimping tools, so it's easy to do. It works fine and if it's what you want to use, then go for it.

Sounds like a interesting project.
Thank you very much. I was actually hoping to hear from you as a lot of the pages that i have been reading up on seam to have comments from you and you have always come across as someone who is knowledgeable.
The soil itself is very rocky and will have to be augered out. I was actually going to pay some of the guys from the electric company who install these things on a daily basis, to do the installation for me. If they aren't able to do it, we have a large auger on the back of the tractor that we can use, but i would rather have the other guys install it as they do it for a living. We have at times turned into their "pole disposal" so they don't have to take them back to the yard. We are on a 100 acre farm and we normally cut them to length to make cattle pens and chutes out of them. So a lot of times we will take all we can get as its great, free farming material for us. I was hoping that they would be knowledgeable enough to get it installed for me. I have read up on the National Electric Code section on grounding communications systems. I have a friend who is an electrician by trade, but he hasn't done any antennas before. I am still going to have him come out and look things over for me. I plan on installing the steps before it goes up. I was just going to install the self tapping tree steps into the pole.

As for the antenna, do you have any experience or recommendation one way or the other as far as the diamond? Do you think i would be better served with something different? I don't want to make a $400 mistake and have to try and change this thing out on my own if i get the wrong thing for my needs.

I went out and measured the pole that i plan on using. Its just over 41' long, 18" diameter at the base and tapers to 13" diameter at the top.
Would you mount the antenna with a heavy duty mast bracket at the top of the pole?
Something like this kind of stand-off bracket http://www.theantennafarm.com/catalo...8743-7728.html, or do you think i would be ok mounting it directly to the side of the mast?

Also, what is your opinion on either the N connecter or the SO 239? It is offered in either one and i need to figure out which is the best one to reduce loss. I have read up a little bit on it and it gets quite controversial at times. I think i am leaning towards the N connecter due to the possibility of longer range UHF use.

Also, seeing how this antenna has 3 radials on it, I'm guessing i don't need any other type of RF ground? At least thats my understanding.

So many questions!!!
Thank you for taking the time to guide me on some of this stuff. I appreciate your opinion on this stuff.
Take care.

Last edited by 19dsniper; 07-16-2017 at 10:24 PM..
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Old 07-16-2017, 10:12 PM
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Quote:
Originally Posted by mmckenna View Post
Give this site a try to see what different coax cables will do for you:
Coax Loss Calculator

Getting a good antenna up high and feeding it with good cable will really improve things for you. If you have the budget for it, I think it's going to turn out well.

If you think you may want to try HF at some point, you might want to have them plant another pole or two on your property. Putting them about 300 feet apart with your radio in the middle would allow you to string up a full length 160 meter dipole. Getting them planted why the guys are there might be cheaper than having them come back later.
Thank you for that link. The line loss calculator is awesome! I can't believe i spent all that time doing the calculations by hand and actually got them correct! Haha!
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Old 07-17-2017, 1:17 AM
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Quote:
Originally Posted by 19dsniper View Post
Thank you very much. I was actually hoping to hear from you as a lot of the pages that i have been reading up on seam to have comments from you and you have always come across as someone who is knowledgeable.
Glad I could help.


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The soil itself is very rocky and will have to be augered out.
OK, the rocky soil usually results in higher ground resistance, so that means you may want to add ground rods. How many you need will depend on the specific conditions where you live.
You might need a network of ground rods to get a sufficient ground.

Check out these guys: Harger Lightning & Grounding
They used to have a lot of data available on their website that may answer your questions. You may have to search around for it. Long ago I got a huge binder from them with training and technical info. I still use it at work.


Quote:
Originally Posted by 19dsniper View Post
I was actually going to pay some of the guys from the electric company who install these things on a daily basis, to do the installation for me. If they aren't able to do it, we have a large auger on the back of the tractor that we can use, but i would rather have the other guys install it as they do it for a living. We have at times turned into their "pole disposal" so they don't have to take them back to the yard. We are on a 100 acre farm and we normally cut them to length to make cattle pens and chutes out of them. So a lot of times we will take all we can get as its great, free farming material for us. I was hoping that they would be knowledgeable enough to get it installed for me.
Probably a good idea. Auguring the hole might be difficult, but actually getting the pole in there will be a lot easier for them.


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Originally Posted by 19dsniper View Post
I have read up on the National Electric Code section on grounding communications systems. I have a friend who is an electrician by trade, but he hasn't done any antennas before. I am still going to have him come out and look things over for me.
Yeah, it's kind of a specialty, most residential/commercial electricians are often unfamiliar with the requirements of a radio system. He should be able to decipher some of the stuff in the NEC, though. What you do need to do, either way, is make sure ALL of your grounds are bonded together. That means the grounding system for your pole and antennas must be bonded to the electrical ground for your home. That needs to be done at the ground rod. Purpose is to keep all the ground potentials at the same level. Having separate grounds with different potentials can lead to all kinds of headaches you don't need.

This gets really critical since a lightning strike will result in a LOT of energy looking for a place to go. Even nearby strikes can induce enough power into your coaxial cable to do damage. It's really important to make sure it's right.
Closest I've been to your area is Fort Stockton, and when I did roll through there it was during one heck of a storm. Just the amount of lightning I saw was enough to scare me. I'd not want to be putting up an antenna out there without some serious grounding in place.


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Originally Posted by 19dsniper View Post
I plan on installing the steps before it goes up. I was just going to install the self tapping tree steps into the pole.
If you get the utility guys to do the install for you, see if they'll give you some of their pole steps. They are a lot better built than the tree stand type pegs. They should also have the removable steps that you put on for the first 10 feet or so to keep people (especially the young ones) from trying to climb it.
The tree stand pegs will probably work OK if that's all you've got.

Quote:
Originally Posted by 19dsniper View Post
As for the antenna, do you have any experience or recommendation one way or the other as far as the diamond? Do you think i would be better served with something different? I don't want to make a $400 mistake and have to try and change this thing out on my own if i get the wrong thing for my needs.
My experience is mostly on the commercial side, but I think a Diamond antenna might be a good choice. They do have a pretty good reputation in the amateur market. Plus, it's not easy to find commercial antennas that will cover the 2 meter and the 70 centimeter bands.

Figure that no antenna is going to last forever. You could do separate VHF and UHF antennas. Either way, don't go cheap, but remember, it's a hobby and you are going to get hobby grade equipment unless you really want to spend $1500 per antenna.

Quote:
Originally Posted by 19dsniper View Post
I went out and measured the pole that i plan on using. Its just over 41' long, 18" diameter at the base and tapers to 13" diameter at the top.
Would you mount the antenna with a heavy duty mast bracket at the top of the pole?
Something like this kind of stand-off bracket http://www.theantennafarm.com/catalo...8743-7728.html, or do you think i would be ok mounting it directly to the side of the mast?
They make specific mounting brackets for putting antennas on tapered poles, but you're going to need to look at places like www.tessco.com or Hutton Communications - Wireless Distribution and Supply Chain Services for that sort of stuff.
Mounting it directly to the pole will work fine, but you probably want to adjust the spacing so it's vertical.

Quote:
Originally Posted by 19dsniper View Post
Also, what is your opinion on either the N connecter or the SO 239? It is offered in either one and i need to figure out which is the best one to reduce loss. I have read up a little bit on it and it gets quite controversial at times. I think i am leaning towards the N connecter due to the possibility of longer range UHF use.
N connector all the way.
By design, they are water resistant, the UHF isn't. However you still do need to pay attention to waterproofing any outdoor connections well.
The N connectors are better performers on higher frequencies.
UHF connectors will work fine for what you are doing, and they are more popular on the amateur radio side. Pretty rare to see them used on the commercial side for base station type stuff.
You can get UHF type connectors for Heliax cable, so that's not an issue.
You'd be wise to choose the N over the UHF connectors if you are building this up from scratch.
For what you are doing, you'd need some pretty expensive test equipment to see the difference between the two, but there's no reason to go cheap or use lower grade connectors.

Quote:
Originally Posted by 19dsniper View Post
Also, seeing how this antenna has 3 radials on it, I'm guessing i don't need any other type of RF ground? At least thats my understanding.
Right. You do need the lightning grounds though.
Lightning grounds, like discussed above, are really important. Also, the commercial standards are to ground the antenna if the manufacturer says to.
Ground the coax near the top of the pole.
Ground the coax near the bottom of the pole with a ground lead going straight down to the ground rod connection.
Ground the coax before it enters the home, use a PolyPhaser (or similar) lightning protection device at the home entrance. This needs to be grounded also. Make sure you get one that is rated for your frequencies and power levels.
Ground your radio equipment.

Done right, a direct strike might damage your antenna, but your equipment might survive. Done wrong, a direct strike will likely destroy your equipment and your home, maybe you, too.
If you ever get a chance, take a look at the grounding systems at a commercial radio site or cellular tower. It's pretty impressive and it helps to visualize how it all works together.

Quote:
Originally Posted by 19dsniper View Post
So many questions!!!
Thank you for taking the time to guide me on some of this stuff. I appreciate your opinion on this stuff.
Take care.
Lots of questions means you're putting a lot of thought into this, and that's a good thing.
Happy to help out.
There are a lot of other guys on here that can provide great info, so hopefully some of them will chip in with their opinions on this stuff. I know there are a few that live out your way, and they may have some useful input on the grounding side.
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Old 07-17-2017, 8:22 AM
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I wish you luck with the Diamond antenna you mentioned. I believe that antenna is in four sections so it has three joints. Those joints are weak spots when it comes to mechanical strength and possible sources of water leakage. If you routinely get high winds at your location, the longer Diamonds, like the X500 and X700, really need some sort of mechanical support to keep them from getting whipped around by the wind. Supposedly the "H" versions are heavy duty and "repeater rated", but I'm still skeptical.
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Old 07-17-2017, 10:50 AM
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Update: I called Diamond antennas this morning and was recommended that i go with a X510HDN due to concerns of high wind in our area. The gentleman i spoke with expected that i would get approximately 60-80 miles simplex on the X700 due to the gain and height of the antenna. This is expected to get a little less. I am still looking for any other recommendations that anyone may have.

This antenna is "rated" as 8.3 db on VHF and 11.7 on UHF. Its only a 1 DB loss compared to the X700, and its $210.00 Cheaper!
He recommended that i paint the antenna with an Epoxy based Non-Metallic paint when i get it. He stated that it already has a protective coating on it but that due to UV, it normally wears out after a year or two. This is rated as a heavy duty antenna with an HD base and N connecter. Its shorter, but will be more rigid and has less joints to mess with. It is also rated 130 watts above the other. I don't plan on ever running that much as my current radio only does 50 watts, but maybe one day...

Last edited by 19dsniper; 07-17-2017 at 10:55 AM..
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Old 07-17-2017, 12:23 PM
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Before installing any "jointed" antenna, I highly recommend getting some heat-shrink tubing from Home Depot or similar store. I slip these over the joiner and then carefully shrink them such that the cover an area 2" above and below the joint(s).
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Old 07-17-2017, 12:35 PM
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Before installing any "jointed" antenna, I highly recommend getting some heat-shrink tubing from Home Depot or similar store. I slip these over the joiner and then carefully shrink them such that the cover an area 2" above and below the joint(s).
Thats a good idea. I didn't think about heat shrink that large in diameter. Beats liquid electrical tape. Thank you for the recommendation. Does anyone recommend using locktite on the internal screws that connect the internal elements of the antenna? I have no idea how this will effect RF/SWR if at all.
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Old 07-17-2017, 1:42 PM
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Locktite would probably be a good idea.

As for the heat shrink, make sure you get "Marine Grade". It has an adhesive interior that will do a much better job of sealing the connection than the normal heat shrink will. When you heat it up the adhesive melts and flows providing a really good seal. I use it on my install jobs and it's worked well.
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Last edited by mmckenna; 07-17-2017 at 2:40 PM..
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Old 07-17-2017, 4:54 PM
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In addition to an electrician doing the grounding, I would recommend Motorola R56 as well as Polyphaser Grounding and Bonding documents for review. It is important that the antenna/pole/tower, the radio system and the building electrical system form a "single point" grounding system. Regardless of your grounding electrodes, you want all of your electronics to float at the same electrical potential. It is voltage differential that causes damage.
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Old 07-17-2017, 6:53 PM
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In addition to an electrician doing the grounding, I would recommend Motorola R56 as well as Polyphaser Grounding and Bonding documents for review. It is important that the antenna/pole/tower, the radio system and the building electrical system form a "single point" grounding system. Regardless of your grounding electrodes, you want all of your electronics to float at the same electrical potential. It is voltage differential that causes damage.
Am i understanding correctly that you are recommending an Air Terminal on this antenna? If so, how would i attach it? This antenna will look something like this when complete:

Unless i pay someone... then it will hopefully look like this when complete:



Im trying to figure out how i would add an Air Terminal to the top of the antenna, when the antenna itself will be the tallest thing on top of the mast? Its not a repeater tower where you typically have a Rx antenna that is higher than the Tx antenna. This antenna will extend from the top of the pole, straight up above it by a good 15'.

Not arguing, just trying to understand if this is what your recommending as its what i could find when looking up Motorola R56. It keeps going back and referencing an "Air Terminal" and soil resistance. I spoke with another gentleman that recommended that because we live on such rocky soil that I actually add some rock salt or Copper Sulfate to the soil to make it more conductive with my grounding rods. He also recommended that i run the Poly Phazer on a separate ground from the antenna ground. Does this still count as a "single point grounding system"?

Last edited by 19dsniper; 07-17-2017 at 6:58 PM.. Reason: I can't spell..
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Old 07-17-2017, 8:36 PM
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Quote:
Originally Posted by 19dsniper View Post
Am i understanding correctly that you are recommending an Air Terminal on this antenna? If so, how would i attach it? This antenna will look something like this when complete:

Unless i pay someone... then it will hopefully look like this when complete:



Im trying to figure out how i would add an Air Terminal to the top of the antenna, when the antenna itself will be the tallest thing on top of the mast? Its not a repeater tower where you typically have a Rx antenna that is higher than the Tx antenna. This antenna will extend from the top of the pole, straight up above it by a good 15'.

Not arguing, just trying to understand if this is what your recommending as its what i could find when looking up Motorola R56. It keeps going back and referencing an "Air Terminal" and soil resistance. I spoke with another gentleman that recommended that because we live on such rocky soil that I actually add some rock salt or Copper Sulfate to the soil to make it more conductive with my grounding rods. He also recommended that i run the Poly Phazer on a separate ground from the antenna ground. Does this still count as a "single point grounding system"?
I never mentioned anything about an air terminal (but your antenna will be one) or use of chemical grounds. Those documents discuss grounding and bonding and the important concept of a single point reference in the grounding system. I suggest a more thorough read of those documents. Or you could simply ignore them, have an electrician install a ground rod (meets code) , and report back in a few months about your expensive lightning damages.

And no, putting a separate ground for a Polyphaser is not a single point grounding system. It is bad practice and the reason you should read and understand these documents.

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Last edited by RFI-EMI-GUY; 07-17-2017 at 8:41 PM..
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Old 07-17-2017, 9:16 PM
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I didn't say you mentioned anything about an air terminal or chemical grounds.

When i searched for the Motorola R56, the returns i received were in reference to using an "air terminal", I had no idea what one was until i ran across it, never heard of one before. Im not trying to be a smart guy.. Thats why i asked the question, "Am i understanding correctly that you are recommending an Air Terminal on this antenna? If so, how would i attach it?" I will search again in reference to the Motorola R56 and see what i come up with, I guess i didn't dig deep enough earlier. I hope you didn't take this the wrong way. I appreciate you taking the time to try and educate me. This is why i stated, "Not arguing, just trying to understand". I have been getting conflicting information either on here, other sites, and even depending on the electrician i ask. Earlier when i called my electrician he didn't have the answer but instead of just whinging it he actually put me in contact with his neighbor who use to install commercial public safety antennas and towers for some large cities. He is an Extra class with a 280' tower on his property and is quite respected in the area where i live. I asked around before talking to him today.

The following is not a statement of fact, just what i was told by him today when we spoke on the phone for a while.

As far as the Chemical ground, he was the one who recommended using copper sulfate or rock salt after a layer of pea gravel once the mast was in the ground. His recommendation was that in using this it allowed the grounding rod to have better connectivity with our rocky soil. His recommendations were as follows:
Antenna on mast: Antenna should be grounded already by means of attaching it to the wooden mast and #6 copper wire.
#6 solid copper from top of mast, attached every 18"- 24" with large staples, all the way to the bottom of the mast and either making multiple loops around the base (looks like the flat electric burner on a stove) or a solid copper plate on the bottom. This line would be attached to an 8' ground rod (or because of the amount of rock we have, (2) 4 foot grounding rods) attached to grounding wire with #6 solid copper wire.
Coax: Skin outer jacket to expose copper on 1/2" Heliax, use a store bought heliax grounding kit or the copper braid from the inside of standard coax to ground coax to grounding rod at the bottom of the pole. (sealing for water intrusion)
-Use a Poly Phazer to ground at the house on a separate ground using either #8 or preferably #6 copper. This is when he mentioned using the copper sulfate to give better connectivity between ground and rod. (his reasoning for this is that seeing how i would only be running 1 radio and 1 antenna on this system, his opinion was that a closed /single ground was more for ground fault protection and less for lightning strikes. He didn't believe that i would have any issues with ground faults with the set up that i will be running.)

My electrician has never done towers before and so he reached out to this gentleman who he knows set up and installed the 911 center and all radio related equipment for a county with the population of 335,000 people. Like i said, right or wrong, i have no idea. This was just what i was told.
I am getting conflicting information and I'm overwhelmed with everything that is flooding in. Im just trying to educate my self as well as i can before frying something. I was trying to go off of someones personal / professional experience.

Again, thank you to everyone who is trying to help, i really am trying to absorb as much of this as i can.

Last edited by 19dsniper; 07-17-2017 at 9:26 PM.. Reason: clarification
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Old 07-17-2017, 10:03 PM
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Quote:
Originally Posted by 19dsniper View Post
When i searched for the Motorola R56, the returns i received were in reference to using an "air terminal", I had no idea what one was until i ran across it, never heard of one before. Im not trying to be a smart guy.. Thats why i asked the question, "Am i understanding correctly that you are recommending an Air Terminal on this antenna? If so, how would i attach it?" I will search again in reference to the Motorola R56 and see what i come up with, I guess i didn't dig deep enough earlier.
An air terminal doesn't attach to the antenna, it attaches to the support structure. It usually is placed above all the antennas and is grounded. They can either be a single rod or sometimes they'll have a fan of smaller wires coming off it.
This makes an attractive place for lightning to hit, and/or static electricity to pass.
If done right, it'll get most of the energy to ground.
Most. Not all. It doesn't negate the need for properly grounding and protecting everything else.


Quote:
Originally Posted by 19dsniper View Post
Earlier when i called my electrician he didn't have the answer but instead of just whinging it he actually put me in contact with his neighbor who use to install commercial public safety antennas and towers for some large cities. He is an Extra class with a 280' tower on his property and is quite respected in the area where i live. I asked around before talking to him today.
It's always a good sign when you ask someone a question they don't have an answer to that they go find it or recommend someone who does.

I think you have a good resource there.

Quote:
Originally Posted by 19dsniper View Post
As far as the Chemical ground, he was the one who recommended using copper sulfate or rock salt after a layer of pea gravel once the mast was in the ground. His recommendation was that in using this it allowed the grounding rod to have better connectivity with our rocky soil.
This is correct.
There are other ways to get better connectivity, though.
Often a number of ground rods are installed. The number needed will depend on the soil resistance. Might be one, might be 20 or more, it all depends. They all get connected together to make that "one point of ground" thing.
Another way to do it is to bury lots of copper wire in the ground. Fanning out from the tower base.
Chemical grounds can help improve a ground rods performance, but it doesn't always last forever. The chemicals will break down or leach away when the soil is moist. Sometimes chemical grounds need to be replenished.

The metallic water pipes can be used as part of your ground, too. I know a guy who had an old well casing on his property. He grounded to that and it worked really well. (no pun intended).

Also, you can install the ground rods somewhere the soil says wet. This can improve conductivity. In a garden, near septic field, etc. Not ideal, but an option.

On high rocky mountain tops radio sites might have several ground rods placed as well as lengths of copper wire buried. I was even at a site once that had copper cable thrown over the side of the peak.




Quote:
Originally Posted by 19dsniper View Post
His recommendations were as follows:
Antenna on mast: Antenna should be grounded already by means of attaching it to the wooden mast and #6 copper wire.
He's right, but industry standard is to ground the coax shield near the top. Most antennas don't have a very good way to attach a ground connection. Relying on lag bolts to hold the antenna against the ground wire coming down the pole isn't reliable. With time and weather the metals will corrode, especially if they are dissimilar metals, and cause the joint to become high resistance.


Quote:
Originally Posted by 19dsniper View Post
#6 solid copper from top of mast, attached every 18"- 24" with large staples, all the way to the bottom of the mast and either making multiple loops around the base (looks like the flat electric burner on a stove) or a solid copper plate on the bottom.
These copper plates are what you would usually find on the base of a utility pole.

Quote:
Originally Posted by 19dsniper View Post
This line would be attached to an 8' ground rod (or because of the amount of rock we have, (2) 4 foot grounding rods) attached to grounding wire with #6 solid copper wire.
Consider more than one ground rod, plus the connection to the home ground rod. If soil resistance is high, adding more ground rods can lower it. More copper in contact with the ground improves the connection.


Quote:
Originally Posted by 19dsniper View Post
Coax: Skin outer jacket to expose copper on 1/2" Heliax, use a store bought heliax grounding kit or the copper braid from the inside of standard coax to ground coax to grounding rod at the bottom of the pole. (sealing for water intrusion)
The manufacturer specific grounding kits work well and can save some time. Not saying the braid connection won't, it just that the kit comes with everything you need and they are relatively cheap. Last time I purchased some I think they were $30 each.

Quote:
Originally Posted by 19dsniper View Post
-Use a Poly Phazer to ground at the house on a separate ground using either #8 or preferably #6 copper.
I strongly disagree with him here. Now, that could be that locally they have learned that certain things work better than what the industry standard is, and in that case I'd pay attention to what he's saying. But, as for the rest of the industry, the single point ground is important. If you have questions, contact PolyPhaser directly and ask them.

Quote:
Originally Posted by 19dsniper View Post
This is when he mentioned using the copper sulfate to give better connectivity between ground and rod. (his reasoning for this is that seeing how i would only be running 1 radio and 1 antenna on this system, his opinion was that a closed /single ground was more for ground fault protection and less for lightning strikes. He didn't believe that i would have any issues with ground faults with the set up that i will be running.)
Not sure exactly what he's going for here, but again, might be a local thing. I'd still disagree, though. If done per NEC, all your grounds are connected and needing a separate ground for "faults" is not needed. You might want to get a second, third or fourth opinion on this.

Consider that if you are getting into amateur radio your needs/interests will always be changing. You'll probably want more antennas down the road, so plan for that now.

Also, when running your ground cable, make it straight, no bends if you can avoid it. You want the lightning having a straight path down to the ground. The ground rod at the base of the pole plus the plate/coil on the pole butt will help. Sharp bends increases the chances of the lightning energy finding an easier or alternate way to get to ground. That might be through something expensive.


Quote:
Originally Posted by 19dsniper View Post
I am getting conflicting information and I'm overwhelmed with everything that is flooding in. Im just trying to educate my self as well as i can before frying something. I was trying to go off of someones personal / professional experience.

Yeah, that sounds normal. Ask 10 people what you should do and you'll get at least 11 different answers.
Good thing the National Electric Code is there to clear up confusion
Like I said above, consider all your advice, but make sure whatever you do meets the NEC. That's what counts. NEC is well proven, that's why its required.

There is a lot of good resources out there. Make sure you know something about the person giving you information. There are a lot of opinions about what you need or don't need. Some people do no grounding or the absolute minimum and get away with it. They sometimes think that makes what they've done is correct. Rather, they may just be lucky.
Don't rely on luck. Lightning doesn't play by our rules.


Quote:
Originally Posted by 19dsniper View Post
Again, thank you to everyone who is trying to help, i really am trying to absorb as much of this as i can.
Glad we can help, however keep in mind that were just a bunch of strangers on the internet. We may be feeding you a total line of BS (but so far no one is). That's why you keep seeing the NEC, R56, and the other standards being quoted. Those are known to work and work well. Cutting corners on something like this, especially in your area, can be dangerous. It's your risk to take, though.
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Old 07-17-2017, 10:56 PM
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In reading more on the NEC, and now finding R56 (Thank you RFI-EMI-GUY), it just randomly reminded me of something he (the gentleman from my earlier phone call) stated that some of the local hams do... I find it interesting, but there is no way in hell that I'm going to try it, EVER. He stated that instead of a PolyPhaser that some guys are using SPARK PLUGS!!! He said that some guys narrow the gap of the spark plug and that somehow works as a makeshift PolyPhaser.... Not this guy! I know there is a lot of learning in amateur radio, and that it can be fun to play around with different things.... but something like this just doesn't sound like FUN learning to me!

Last edited by 19dsniper; 07-17-2017 at 11:34 PM..
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Old 07-18-2017, 1:21 AM
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I wanted to weigh in my 2 cents on this topic;
.
Lightning-- its a favorite of mine and it seems quite a popular favorite here in the recent forums.
.
19dsniper- to all the other's advice you've gotten I'll suggest you read this:
.
http://lightningsafety.com/nlsi_lhm/IEEE_Guide.pdf
.
Professionally (and for what its worth, I am a member of the organization that publish'd that guide) I adhere to all the basics in it. Lightning suppression is not rocket science, but it plays by rules that aren't often common sense.... like 'floating' the system's ground. If you are really into this subject, there is a plethora of similar publications** but take deep breathe before you immerse yourself in them- they get quite involved ...
.
Since you've received a lot of information from others, I'm going to bow out of the discussion unless you've something specific of me.
.
Oh... except for this--
.
..............The use of conductive enhancing chemicals; copper sulphate, mineral salts-- I have never seen them used professionally-- in fact I have seen warnings against their very use. They pose a potential toxic hazard to wells, grazing lands,____________(fill in the blank.) Increase your earth connection in another way, if you must.
The last thing you want to see is guys in Haz-Mat suits out in your fields with a court injunction ! Besides, the advantage you gain temporarily (the stuff undergoes diffusion and weakens in what ever minor effects it might have-) is offset by the amount you want to spread-- and pay for. Plus the stuff is corrosive, especially to aluminum..
.
Me, if I found someone had spread Blue Stone on my pastures I would get my cowboys out after them --and it would not be for an invite to an ice cream social.....
.
Do your home work on the subject, 19dsniper- but don't obsess over lightning. Look about you- at all the power poles, high tension pylons- and what are the chances of their receiving direct strikes.*** Worry most about the induced surges- you can do something about those- and they are the source of 99.99% of your damage. If the gods send you a direct strike- well, it was just Kismet... and Lady Luck is going to decide that outcome...........
.
Cheers, Cowboy ! .........
.
.......................CF
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__________________________________________________ _________
**
http://sites.ieee.org/sas-pesias/fil...o-Verdolin.pdf
.

http://paginas.fe.up.pt/~ee04104/dis...ubstations.pdf
.
***
Also remember, a well designed antenna structure acts as an 'air terminal' ---which can ('can', as is 'might', as in 'maybe')-- disperse a static charge before it gains potential enuff to result in a direct arc. Look at the static dispersal 'thing-ys' that surround power company transformer 'farms'...... those "Fuzzy Balls?"... for instance

Last edited by Coyote-Frostbyte; 07-18-2017 at 1:37 AM..
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