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-   -   Using Chain link top rail for mast (http://forum.tvfool.com/showthread.php?t=16075)

wado66 29-Aug-2016 6:00 PM

Using Chain link top rail for mast
 
I was looking a hardware store at chain link top rail poles.
I thought this may be a good option for mounting my antenna to. I can get them in diameters of 1.31 and 1.66.
I can get wall thickness of 14, 16, and 17 gauge and 10ft. or 20ft. lengths.
Has anyone else used these poles?
What are the pros and cons of using this for an antenna mast?

Stereocraig 29-Aug-2016 7:02 PM

Quote:

Originally Posted by wado66 (Post 56094)
I was looking a hardware store at chain link top rail poles.
I thought this may be a good option for mounting my antenna to. I can get them in diameters of 1.31 and 1.66.
I can get wall thickness of 14, 16, and 17 gauge and 10ft. or 20ft. lengths.
Has anyone else used these poles?
What are the pros and cons of using this for an antenna mast?

Those are a favorite of most of the people in this forum.
Base the diameter on your brackets and U bolts.
Gauge? 14 would be strongest, but maybe its cost and weight wouldn't be worth it.
20' w/o guying, may, or may not be pushing it, but that depends on your situation.

wado66 29-Aug-2016 7:37 PM

The antenna will be mounted on a 2 story house.
I plan on attaching it to the eave with this bracket.
http://i183.photobucket.com/albums/x...na%20mount.jpg

If I mounted a 15ft pole to this and antenna on top you think I would be ok for sturdiness?
Sorry, but I'm a noob cutting the cable for the first time and a little nervous about setting this all up.
The antenna will be using would be a CM-2020 or CM-3020.

Stereocraig 29-Aug-2016 9:06 PM

I have no doubt that the bracket itself is adequate, but I would be concerned w/ that 3/4" fascia board and whether it would be meaty enough on its own.
You could probably use some 2X4 backing strips inside the attic.
If you were real lucky, you may even hit a rafter, or truss.
Be sure to drill pilots for the lag bolts, because they're cheap and snap easily.

I'd also like to see as much distance as possible, between my upper and lower brackets, to minimize twist.

bobsgarage 31-Aug-2016 4:54 AM

Chain link top rail.
 
Quote:

Originally Posted by wado66 (Post 56094)
I was looking a hardware store at chain link top rail poles.
I thought this may be a good option for mounting my antenna to. I can get them in diameters of 1.31 and 1.66.
I can get wall thickness of 14, 16, and 17 gauge and 10ft. or 20ft. lengths.
Has anyone else used these poles?
What are the pros and cons of using this for an antenna mast?

I currently use a 21' 1 3/8" SS-20 top rail. It is approx. .90" wall thickness. I don't know what that translates to in gauge.

However, in a 40 MPH wind it twisted enough to bother me. So, I hauled it back down and sleeved the inside with SCH 40 galvanized water pipe. It only comes in 10' sections, so I put a 12mm deep socket between the two sections (1/2 length inside each end for sleeving, mainly for alignment) welded them together, painted the welds and hammered my new 20' reinforcement inside of my 21' top rail. Every 4 feet or so, I drilled holes through the double wall pipe and reinstalled it to my main mast and rotator. It doesn't twist anymore. ;)

The upper mast I described is heavy, especially with 2 antennas but I have rotator upper bearings to carry some the weight.

My main mast is 1 5/8 SS-40 industrial top rail. It is quite stout. It goes into a 10 foot tripod though and uses two sets of guy wires.

In your case, the SS-20 would be minimal. I also found out that 1 3/8 top rail comes in SS-40 but the fence company next door doesn't carry it. Maybe near you? Just don't use "tubing" it is thin.

I personally don't like those eave mounts because it is only as strong as the wood it attaches to. And, unless the mast goes to the ground and the eave mount is there for stability, you better keep your mast less than 10 feet.

I think you can go higher, just join two 21' Pipes together with sleeves all the way to the ground and use your eave mount as a stabilizer, like a wall mount. In this way, the entire weight of your assembly is transferred to the ground.

1' 5/8" SS-40 would be good for that and they have a outer sleeve for joining them or my favorite is the neck down of the last six inches where you stick one pipe into the other. Kind of like exhaust pipe, where a joining piece has the outside diameter reduced to slip inside the receiving piece but on a heavier duty level.

Sorry, I'm rambling on the details. I didn't ask earlier, how high that roof peak is AGL ?

rickbb 31-Aug-2016 3:16 PM

Quote:

Originally Posted by wado66 (Post 56097)
The antenna will be mounted on a 2 story house.
I plan on attaching it to the eave with this bracket.


If I mounted a 15ft pole to this and antenna on top you think I would be ok for sturdiness?
Sorry, but I'm a noob cutting the cable for the first time and a little nervous about setting this all up.
The antenna will be using would be a CM-2020 or CM-3020.

I think that setup would be fine, but 15ft would be about my max to go without using any guy wires. At 20' definitely use a guy wire system.

bobsgarage 2-Sep-2016 3:15 PM

No Big Antennas
 
Quote:

Originally Posted by wado66 (Post 56097)
The antenna will be mounted on a 2 story house.
I plan on attaching it to the eave with this bracket.
http://i183.photobucket.com/albums/x...na%20mount.jpg

If I mounted a 15ft pole to this and antenna on top you think I would be ok for sturdiness?

Sorry, but I'm a noob cutting the cable for the first time and a little nervous about setting this all up.
The antenna will be using would be a CM-2020 or CM-3020.

The 2020 doesn't have a lot of cross section for wind load, so for 15 feet up without guy wires, you would probably be OK. The 3020 is a monster at 12 feet long. I would not put that up 15 feet on an eave mount like that. Unless you run the mast to he ground.

Do you need a VHF Lo antenna? VHF Lo antennas are too big to be practical, especially if you don't have any VHF Lo stations in your area...

If you choose a a VHF HI/UHF combo antenna it will have a smaller profile being more wind worthy. Then you could use

Like Stereocraig said " I'd also like to see as much distance as possible, between my upper and lower brackets, to minimize twist." And maximize strength.

The higher you go, the more wind leverage against your mast. If you use a stout enough mast, I wonder what would happen with the eave brackets in a heavy wind?. The brackets look strong but how much wood is on the other side where the screws go?

You really don't have the mounting area for guy wires on the drop off side of the roof, so that's out. Guys wires only on the roof side of your mast would only help on wind gusts coming from that direction.


Hey, in your photo, I see a higher roof. Bonus! You could put a tripod up there and gain 8-10 feet just by going up to the upper level peak. I'll bet you will get much better reception up there.

You could use your eve mount for something else, like an FM antenna or whatever you need since it is already there.

wado66 2-Sep-2016 4:46 PM

Sorry, I should have been clearer on the picture. This is a stock photo from the internet I was using to show the mounting hardware I was thinking of using. I have nothing purchased or mounted so far. Just trying to get my ducks in a row.
My roof has no additional eaves.
I do not need VHF Lo.
The antenna I have my eye on is the Channel Master CM-3020.
To gain added rigidity to the pole I will be running it all the way down into the ground.
I was looking at the eave last night and think I may have a plan to strengthen the antenna from wind. About 4' to the left is my chimney. I may run some type of bracket from the chimney to the pole. Can only help.
I really really appreciate all of this input to help in my decision making. Very useful info.
I am going to crawl up in the attic this weekend to see if I can get to the area the mount will be bolted. Would like to be able to add some 2X4 pieces to bolt into if I can get there.

rabbit73 2-Sep-2016 5:55 PM

Quote:

I do not need VHF Lo.
The antenna I have my eye on is the Channel Master CM-3020
If you do not want VHF-Low for real channels 2-6, why did you pick an antenna with big elements for VHF-Low?

wado66 2-Sep-2016 7:16 PM

I was just going under the technical theory "bigger is better."
Am I overkilling?

bobsgarage 2-Sep-2016 11:47 PM

Quote:

Originally Posted by wado66 (Post 56175)
I was just going under the technical theory "bigger is better."
Am I overkilling?

yes that would fall under the category of overkill. Having VHF low elements on your antenna will not help you pick up VHF Hi or UHF. That is what the one good benefit of the channel reassignment. Smaller antennas.

I recently took down my Radio Shack VU210 XR. A full 16 feet long and 8 or 9 feet wide. To be honest I don't know how it made it 15 or 16 years. No broken elements.

It was OK until I decided to raise my masts and then it became a windmill. These were only 35 MPH winds:

https://www.dropbox.com/s/aemgkbyza1...20006.MTS?dl=0

The CM-3020 is Too much antenna for the channels available. And that is true in most markets.... VHF LO is a novelty now.

rabbit73 3-Sep-2016 11:48 AM

Quote:

I was just going under the technical theory "bigger is better."
That is usually true.
Quote:

Am I overkilling?
Not too much. I just wanted to be sure you knew the difference in size between an antenna for VHF-Low + VHF-High + UHF and an antenna for VHF-High + UHF.

VHF-Low: real channels 2-6, 54 to 88 MHz
VHF-High: real channels 7-13, 174 to 216 MHz
UHF: real channels 14-51, 470 to 698 MHz

Your report:
http://www.tvfool.com/?option=com_wr...e2cbd4dffce5f3

Channel Master CM-3020 AKA Advantage 100
http://www.channelmaster.com/Digital..._p/cm-3020.htm

Bandwith 54 to 216 and 470 to 700 MHz
VHF Gain 8.6dB
UHF Gain 9.5dB
Max Element Width 95"
Boom Length 152"
Weight (product) 7 lb
Wind Resistance (at 100 mph, no ice) – 37 lb

CM-2020 AKA Digital Advantage 100
http://www.channelmaster.com/Digital..._p/cm-2020.htm

Bandwith 174 to 216 and 470 to 700 MHz
VHF Gain 7.5dB
UHF Gain 10dB
Max Element Width 61"
Boom Length 90.5"
Weight (product) 4.5 lb
Wind Resistance (at 100 mph, no ice) – 38 lb

The final decision is up to you.

Stereocraig 3-Sep-2016 12:31 PM

Quote:

Originally Posted by wado66 (Post 56173)
Sorry, I should have been clearer on the picture.
I do not need VHF Lo.

You could also use the 3020 to feed your FM tuner.

bobsgarage 3-Sep-2016 12:58 PM

Quote:

Originally Posted by Stereocraig (Post 56186)
You could also use the 3020 to feed your FM tuner.

Really? I know you have to be joking, I know you got a great sense of humor.

Seriously though, He wants to use an eave mount. The 3020 is pretty large antenna if he just wants FM as an extra to UHF/VHF Hi... Most of the size of that antenna is wasted.

He can get one of these, if he wants FM:

http://www.solidsignal.com/pview.asp...R6010)&c=AM-FM Radio Antennas&sku=777786197681

Well, time to watch the weather...

Stereocraig 3-Sep-2016 1:10 PM

Quote:

Originally Posted by bobsgarage (Post 56187)
Really? I know you have to be joking, I know you got a great sense of humor.

Seriously though, He wants to use an eave mount. The 3020 is pretty large antenna if he just wants FM as an extra to UHF/VHF Hi... Most of the size of that antenna is wasted.

He can get one of these, if he wants FM:

http://www.solidsignal.com/pview.asp...R6010)&c=AM-FM Radio Antennas&sku=777786197681

Well, time to watch the weather...

I guess I should've clarified that I would do that if I already had one, but I wouldn't go out of my way to buy one just because it is capable of receiving FM.

bobsgarage 3-Sep-2016 1:23 PM

Quote:

Originally Posted by Stereocraig (Post 56189)
I guess I should've clarified that I would do that if I already had one, but I wouldn't go out of my way to buy one just because it is capable of receiving FM.

Yeah, I re-read it and he hasn't bought any antenna yet. Good for him. :)

Maybe he can give up on the idea of an eave mount, unless he goes with something small.

A 91 XG on a 5-10 foot mast wouldn't be too bad I guess, but a an HD7698P, well, that's gonna have more windload.

rabbit73 3-Sep-2016 2:19 PM

wado66 also has another thread:

How do I read the topo map
http://forum.tvfool.com/showthread.php?t=16077

Dividing the problem into two threads makes it harder to help him. Keeping it all on one thread would be better.

His problem channel is WSMV NBC real channel 10, so a 91XG wouldn't do it. He might even need an MCM 30-2476 that can tilt up for VHF because of the hill plus a UHF antenna, if a UHF/VHF combo antenna doesn't work for NBC.

http://www.tvfool.com/?option=com_wr...e2cbd4dffce5f3

He can't use a preamp because it will be overloaded, so he must depend upon antenna gain.

bobsgarage 3-Sep-2016 6:02 PM

The problem is split between two threads.
 
Quote:

Originally Posted by rabbit73 (Post 56193)
wado66 also has another thread:

How do I read the topo map
http://forum.tvfool.com/showthread.php?t=16077

Dividing the problem into two threads makes it harder to help him. Keeping it all on one thread would be better.

His problem channel is WSMV NBC real channel 10, so a 91XG wouldn't do it. He might even need an MCM 30-2476 that can tilt up for VHF because of the hill plus a UHF antenna, if a UHF/VHF combo antenna doesn't work for NBC.

http://www.tvfool.com/?option=com_wr...e2cbd4dffce5f3

He can't use a preamp because it will be overloaded, so he must depend upon antenna gain.

Thanks for clarifying that Rabbit. I was wondering where his TV full report might have been. I was thinking it was more of an installation problem, and it is, but there's more to it than I thought.

You are correct. It is much easier to understand the problem when it's all in one thread.

I've got to say I'm quite happy with my 30 - 2476.

wado66 3-Sep-2016 6:14 PM

Sorry about that guys. I see where that info in this thread would have been helpful for you.

wado66 3-Sep-2016 6:18 PM

This is an actual picture of my home where I want to put the antenna just so you know what I am dealing with.
http://i183.photobucket.com/albums/x...05_resized.jpg


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