Putting up a 6meter galvanised mast.

[Kameelperdza]

I want to get two 6 meter galvanised 50 mm tube and put it up at 2 different places. Then use three 15cm tripod brackets to mount the mast to the side of a building. I want to put all three tripod at the bottom to give the mast added strengh and also maybe help with the swigging in the wind.

I have two option on how to put up my antenna's

1. At the moment i have 1mter lmr400 cables which i can use. But then i will have difficulty getting to the box becos it is at the top of the tower and i dont have a cherry picket to get up there. My mast will also have more weight if i put the ut7 box at the top of the tower.

2. I can get 4meter lmr400 cable and then put the ut7 at the bottom of the mast. But then i have dbm loss.The good thing is that i will be able to get to the routerboard if there is any work to be done. And also it will take some weight of the top of the mast.


Which one is the best? I went to the store and got 0.9mm thick 100meter galvanised steel wire which i want to use as strain wires. Want to put 4 in the middel and 4 at the top. The antenna i want to use is one 12dbi 2.4ghz omni, a 15dbi 5ghz sector and a 24dbi 5ghz grid.

Any help or advice would be appreciated.

 

[spiderz]

Use stay-cables.
Talk to Densweep on ptawug, think he had a 12m mast, 3 pieces put together.

 

[Kameelperdza]

Thank you i will try to contact him. He is not currently online

 

[Pilgrim]

Your loss on a LRM400 will by very, very little. Rather go 4m.

Many of our high sites have 4m lrm cables.

 

[Kameelperdza]

That is good news. I wonder how much does a 6meter galvanised steel mast weigh

 

[F4ckn]

I can only guess, i helped Netgnome take his down and put it back up again... With 3 grids it weighs a lot. I battled to raise it in the mount by myself,

 

[Kameelperdza]

I can only guess, i helped Netgnome take his down and put it back up again... With 3 grids it weighs a lot. I battled to raise it in the mount by myself,

What cables does he use to help support the mast? And is hes mast mounted to the side of a building? And doe she use tripod brackets to mount it? Do you think the cables i want o use will work? 0.9mm galvanised steel wire.

My friend said he will help me to put it up.

 

[KillerB]

Your loss on a LRM400 will by very, very little. Rather go 4m.

Many of our high sites have 4m lrm cables.

Well the loss on an 4m cable and a 20m cable are like 0,00001db on the LRM400 cable, and please dude use the advice stay away from omni's that a waits of money.....

 

[Kameelperdza]

Well the loss on an 4m cable and a 20m cable are like 0,00001db on the LRM400 cable, and please dude use the advice stay away from omni's that a waits of money.....

Thanx wish i knew that before i bought mine.I will out up another rb433 and then put 3 120' sectors on it.

 

[KillerB]

the cable will work and its not necessary to do that six times if you can pull the stays from about 1.5m from the top in 3 or 4 different ways the the wind won't harm the mast it worked for me till i moved every thing..

 

[Kameelperdza]

Thanx i keep that inmind. 1,5m from the pole. I want to get two 6mter poles and then put one omni, one sector and one grid on it. That is why i need six 4 meter cables. I can always just use my 1 meter cables to save money but then i will have trouble getting to the routerboard.

 

[KillerB]

Thanx i keep that inmind. 1,5m from the pole. I want to get two 6mter poles and then put one omni, one sector and one grid on it. That is why i need six 4 meter cables. I can always just use my 1 meter cables to save money but then i will have trouble getting to the routerboard.

If u put your grid the lowest then u can use the 1m cable and u could still get to the routerbourd if needed it could save u a buck or 2, in the mean while

 

[Obelix]

Your loss on a LRM400 will by very, very little. Rather go 4m.

Many of our high sites have 4m lrm cables.

I agree - and a UT7 up on a pole is gonna be like a sail.

What freq do you wanna run ? LMR400 at 2.4 GHz freq gives you 0.2dBi loss per meter, whereas on 5GHz you get 0.38 dBi loss. theres a website you can look this up on.

A general rule of thumb : for every 3dBi loss you loose half your signal strength ( its not a linear thing )

 

[Obelix]

That is good news. I wonder how much does a 6meter galvanised steel mast weigh

Its heavy.... I have 2 joined together ;-)

It takes 3 ppl to maouver it when i need to take it down.

I use 3mm pvc coated steel cable stays. Theyve survived all the heavy windows weve had in PE over the last 6 months....

 

[Kameelperdza]

cant wait till moday. then i will get the 6meter pole, the 4 meter cable and the two 27dbi grids.

 

[kilos]

Its heavy.... I have 2 joined together ;-)

It takes 3 ppl to maouver it when i need to take it down.

I use 3mm pvc coated steel cable stays. Theyve survived all the heavy windows weve had in PE over the last 6 months....

How do you raise a 12m pole with an antenne & Outdoor box on

Do you build a pivot system to lever it up ?

 

[Obelix]

Nothing that fancy. Drop it down to the ground, and then swivel the bottom out

Putting it up is more difficult, but essentially, lean it on the roof next to the chimney. then push it up, with the person standing on the chimney guiding it upwards until it reaches the brackets, then hoot the brackets around the pole and start hoisting it up until its at the top, then tighten the brackets ( U-bolts )

The whole success of this method is based around a very strong wall that is bolted to. If i ever have to redo this, 'll start with a nice big flagpole. At least they tilt down easilly......

 

[kilos]

A general rule of thumb : for every 3dBi loss you loose half your signal strength ( its not a linear thing )

Thats why the Ubiquiti Bullets are great in a way with no LMR400 needed if you screw it straight onto the N type connector, no big Outdoor enclosure

There is a disadvantage if it sticks out like this

Better this way

Love this method that portcullis posted of the flagpole with a counter weight

Full View

Schematics on how to build it

Tilt Mechanism

 

[Kameelperdza]

The pole at the one location is finally up. It been a struggle to put it up. My signal is better but it will be better when i put the other 6meter pole on the roof of my house.My signal is now -77.

The other problem is that the bloody trees is 20meter high. I cant wait to test the signal when i have finished outting up the other pole. What is the chances that lightning can strike my omni?.

 

[kilos]

What is the chances that lightning can strike my omni?.

Very possible, put a lightning arrestor inline from the Omni -> lightning arrestor <-> Routerboard