70 foot antenna tower advice please for side mount

[Blackcat630]

The wireless internet people that live around me in the sticks use like 30-40 ft of light weight TV antenna tower then they u bolt like 30+ft of light dudy mast starting around 10 ft below the top of the tower for support.. some dont even have a nose cone section. Dont know how they would go about mounting an antron let alone a beam on this type of setup..?
This LONG pipe is fine to support the 1/4 sq ft windload of the internet antenna but I wouldn't mount a discone above it let alone a 11 meter antenna..

 

[543_Dallas]

In Ontario Ca most of the rural internet providers use a point to point wireless system which was (when I was there) government subsidized. My point to point distance was about 20km. My barn had high speed wifi as they used a router as a signal boaster because the distance was thst far to the house. No problems with tower height as long as the jnternet company installed.

I'm not familiar with Canadian rules so I don't understand how that's relevant. The tower is not the issue. Where he puts the CB antenna on that tower may or may not be legal if he lives in the US.

Our rules say the max height can be no more than 20 feet above the structure it's mounted to or 60ft max height.

I guess that means antennas like the imax 2000, and every other antenna over 20 ft long are illegal antennas.

 

[xm49north7]

I have to ask if this is for cb or ham use. Unless the rules have changed in the last 10 years the 70 ft tower is not legal. I don't have anything against it but you said you ran legally in a recent post.

This is for cb ==27 mhz== I have searched out government web sites for info but there is just to much to wade through. I will keep looking.

 

[guitar_199]

I just looked at Part 95 and it says....

-------------------
{A} "Antenna" means the radiating system (for transmitting, receiving or both) and the structure holding it up (tower, pole or mast). It also means everything else attached to the radiating system and the structure.
{B} If your antenna is mounted on a hand-held portable unit, none of the following limitations apply;
{C} If your antenna is installed at a fixed location (whether receiving, transmitting or both) it must comply with EITHER one of the following:
[1] The highest point must not be more than 20 feet (6.10 meters) higher than the highest point of the building or tree on which it is mounted;
or
[2] The highest point must not be more than 60 feet (18.3 meters) above the ground.
{D} If your CB station is located near an airport, and if your antenna structure is more than 20 feet (6.10 meters) high, you may have to obey additional restrictions. The highest point of your antenna must not exceed 39.37 inches (1 meter) above the airport elevation for every 109.36 yards (100 meters, 1 hectometer) of distance from the nearest point of the nearest airport runway. Differences in ground elevation between your antenna and the airport runway may complicate this formula. If your CB station is near an airport, you may contact the nearest FCC field office for a worksheet to help you figure the maximum allowable height for your antenna.
WARNING: Installation and removal of CB station antennas near powerlines is dangerous. For your safety follow the installation directions included with your antenna.
------------------

So {A} tells that the rule applies to the tower as well as the antenna.... but I wonder....

Since the tower was NOT put up for the primary purpose of "being a CB installation" and he gained legal permission to mount his antenna to that tower.... would it still apply?

Further still.... if he honored the INTENT of the rule and mounted his antenna such that the top does not exceed 60' would they be that picky?

I can certainly see support for this issue in both directions...... but.... there we are....

And... who is going to notice?

I have to ask if this is for cb or ham use. Unless the rules have changed in the last 10 years the 70 ft tower is not legal. I don't have anything against it but you said you ran legally in a recent post.

 

[Bow]

And... who is going to notice?

That is exactly what I was thinking....

However...

Is the tower they are putting up able to handle any decent 11 meter antenna?

If nothing else, you could fab up a 1/4wave Ground plane with a 102" stainless whip and mount that on the top... very low wind load

 

[xm49north7]

That is exactly what I was thinking....

However...

Is the tower they are putting up able to handle any decent 11 meter antenna?

If nothing else, you could fab up a 1/4wave Ground plane with a 102" stainless whip and mount that on the top... very low wind load

I will most likely go with one of my full wave loops off the side, these weigh like maybe 1.5 pounds in total, 3 spars, 6 feet long 3/4" pine, I put one in the middle at the feed,
and some #18 wire, , Having great luck with these at 40 feet right now.

 

[Bow]

That would do it

 

[guitar_199]

I FLAT OUT like that!!!!!!!!

I will most likely go with one of my full wave loops off the side, these weigh like maybe 1.5 pounds in total, 3 spars, 6 feet long 3/4" pine, I put one in the middle at the feed,
and some #18 wire, , Having great luck with these at 40 feet right now. View attachment 29298

 

[xm49north7]

I FLAT OUT like that!!!!!!!!

I have built 2 of these so far, Very quiet, simple, cheap, easy to tune for swr, easy to hang, can be rolled up and put in the car for camp comms. I built a moxon, a j-pole , 2 dipoles, and found for my location this one worked the best for me. Has really good receive, and had the best send of the bunch. I could not get the moxon to tune well. Loops take a nice swr across the board. No complaints. Almost perfect omni, Very happy with the loops. Stats say up to 2 dbi better than a dipole. Gets out skip for me every day on stock watts ssb, have not had much testing locally, but have got out 30 kilometers,and as far as 20 to mobiles a number of times. I am told these work like a pair of phased vertical dipoles, models show the top and bottom do not radiate much, it is the 2 side wires doing the work.

 

[guitar_199]

Does the length to width ratio matter much? How wide versus how tall?

Thanks!

I have built 2 of these so far, Very quiet, simple, cheap, easy to tune for swr, easy to hang, can be rolled up and put in the car for camp comms. I built a moxon, a j-pole , 2 dipoles, and found for my location this one worked the best for me. Has really good receive, and had the best send of the bunch. I could not get the moxon to tune well. Loops take a nice swr across the board. No complaints. Almost perfect omni, Very happy with the loops. Stats say up to 2 dbi better than a dipole. Gets out skip for me every day on stock watts ssb, have not had much testing locally, but have got out 30 kilometers,and as far as 20 to mobiles a number of times. I am told these work like a pair of phased vertical dipoles, models show the top and bottom do not radiate much, it is the 2 side wires doing the work.

 

[xm49north7]

Does the length to width ratio matter much? How wide versus how tall?

Thanks!

No, Ideal where porlarization is not important, round is best, as in a circle, it encloses more area. I went 6 feet wide by 12 feet tall to prefer a little longer length in the verticle. Square would again enclose more area, which is said to be more efficient. I just went by pics I had seen on the web, and went with this kinda by eye. What matters is you have the full wave of wire. aprox. 36 feet. I mean you would not want the wires a foot apart, and 34 high, your getting less than a quarter wave apart. I think this is a a good form. Perhaps some of the antenna modelers on here will know more. There very well could be an ideal size. I would be interested to know as well. Your welcome to repost this in the antenna section, some good guys following that, they model up stuff, and are very savy. I mean if it would be better in different measurements, I would build it tomorrow. I am into these loops. I like them. So any new info would be very cool.

 

[guitar_199]

One last thing....
Is there any reason that the feed could not be in the middle at the bottom? It seems to me like running that cable up and then hanging it out to the side where the side of the loop will have to bear the little bit of extra weight.... the bottom just seems natural to me.

Any comment on that?

No, Ideal where porlarization is not important, round is best, as in a circle, it encloses more area. I went 6 feet wide by 12 feet tall to prefer a little longer length in the verticle. Square would again enclose more area, which is said to be more efficient. I just went by pics I had seen on the web, and went with this kinda by eye. What matters is you have the full wave of wire. aprox. 36 feet. I mean you would not want the wires a foot apart, and 34 high, your getting less than a quarter wave apart. I think this is a a good form. Perhaps some of the antenna modelers on here will know more. There very well could be an ideal size. I would be interested to know as well. Your welcome to repost this in the antenna section, some good guys following that, they model up stuff, and are very savy. I mean if it would be better in different measurements, I would build it tomorrow. I am into these loops. I like them. So any new info would be very cool.

 

[xm49north7]

One last thing....
Is there any reason that the feed could not be in the middle at the bottom? It seems to me like running that cable up and then hanging it out to the side where the side of the loop will have to bear the little bit of extra weight.... the bottom just seems natural to me.

Any comment on that?

Yes if it is bottom fed, it becomes horizontally polarized, like a horizontal dipole, not good for local coms, to other upright antenna. If side fed, it is an upright antenna, think vertical dipole, good for locals.

 

[binrat]

XM,
Have you tought about a half square?? I have 1 for portable work. Seems to work great.

 

[Shadetree Mechanic]

Awesome antenna, I am going to find some wire tomorrow. Something inside me wants to put two of these on a beam...