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Duramax08
To The Moon
Premium
join:2008-08-03
San Antonio, TX

How to build a antenna pole or (mast)

Our new house is about done. I was planning not to bring my antenna over to the new house (about 25 feet in the air) since AT&T said I could get DSL, but they lied once again so now gotta live with my cricket modem for now. The antenna pole or "mast" was a old telescopic pole we had laying out in the back. That sucker was a PITA to raise and I just dont feel like doing it again. If anything, Take down the existing pole, take the antenna off and put it on the new house. I could probably get away by mounting it near or around the roof but I would prefer a pole or mast due to trees.

My question is, whats the best way to build a pole or mast? Was thinking of taking a trip to lowes or home depot to see what I could use. I got no clue where to stop so I thought Id stop by here and get some ideas.


WHT

join:2010-03-26
Rosston, TX
kudos:5
What kind of Cricket modem? USB? Ethernet?


Duramax08
To The Moon
Premium
join:2008-08-03
San Antonio, TX
usb. Unless you know of a ethernet modem....


WHT

join:2010-03-26
Rosston, TX
kudos:5
Some USB cellular modems have a problem with even a 6 foot USB cable. Using a 15 foot one may not work. I'd try a long USB cable on your modem first before you build up a mast.


Duramax08
To The Moon
Premium
join:2008-08-03
San Antonio, TX
No, I have a ext antenna. my usb modem is right next to me.


WHT

join:2010-03-26
Rosston, TX
kudos:5
Figure on $100 for a 40 or 50 ft run of LRM-600 coax and adapters.

Nevermind, OP already has antenna.


Daarken
Rara Avises
Premium
join:2005-01-12
Southwest LA
kudos:3
reply to Duramax08
The OP wants TIPS on how to CONSTRUCT the POLE, not on the length of USB cable, or how much LMR400 he needs.

I built an OTA antennae for my father a few years ago,
I took a J-Mount (The kind used to mount a DTV Dish) bolted it to the patio eave, Then I took 3 - 36"x1-1/4" diameter modular pipes (It was the support arms for one of those low cost above ground swimming pools you buy at wal-mart) and butted them all together and stabbed it into the J-Mount. I then attached the OTA Grid antennae and tie-strapped the cable to the pole.
I then elevated the mast and rotated it towards the nearest major city (20 miles away). Surprisingly the antennae has last over 2 years having a great signal and with over 13 channels to view.



--
Getting it Done.


Duramax08
To The Moon
Premium
join:2008-08-03
San Antonio, TX
Thanks for the post. did you mount it to steel or wood? Hard to tell in the pic.


Daarken
Rara Avises
Premium
join:2005-01-12
Southwest LA
kudos:3
steel beam, but remember you want to provide a good ground for it, and a lightning arrestor.
--
Getting it Done.


WHT

join:2010-03-26
Rosston, TX
kudos:5
reply to Daarken
said by Daarken:

The OP wants TIPS on how to CONSTRUCT the POLE, not on the length of USB cable, or how much LMR400 he needs.

It's called proper planning. Sure, we can give ideas on how to construct a mast...but if the rest doesn't work, then he wasted time building his mast.

As for the satellite dish j-pole mount as pictured...very bad idea. A previous WISP used to do that and I know of at least a dozen installs where that method failed for different reasons.

1) The lateral supports depends solely on the friction of the single alignment bolt. Eventually vibration will deform the pole pipe and the pole will slip down.
2) There is no cross lateral support, other than the bolt holding the flanges of the footpad. They will eventually work out.
3) The eave is likely 4"x1" pine and the upper footpad bolts will eventually work out if lower bolts aren't used.

We use j-poles and we use 1-1/4" EMT ten foot extensions, but with improvements. Either electric strut materiel or a footpad extender, and then a pair of struts about a foot up the mast.

If the antenna has a low wind load, you can use two top-rails for chain link fence, and the coupler around the swagged end.


Daarken
Rara Avises
Premium
join:2005-01-12
Southwest LA
kudos:3
What, you responded to the OP's comment not once but twice without grasping the intent of his post.
I will easily concede that the solution I provided is not meant as a proper or long term solution to mounting an OTA antenna or any other type of antenna. It was the only solution available at the time.

So instead of pointing out the obvious flaws of my installation, why don't you provide the OP assistance with his question.

BTW, The eave is 1/4" steel beam, not wood, as per the reply just above yours.
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Getting it Done.

LLigetfa

join:2006-05-15
Fort Frances, ON
kudos:1
The OP has not provided enough useful information. All we know is the old house had a mast. There is mention of "25 feet in the air" but we don't know if that is the old house or the new house.

The height is relative to the terrain and the trees in relation to the tower, all of which are a mystery. We don't know anything about the house construction, roof style or height, etc.

Then there are concerns about lightning protection, cable lengths and runs, etc.

One needs to start with a site survey to ascertain just how high it needs to go and then take it from there.
--
Strange as it seems, no amount of learning can cure stupidity, and formal education positively fortifies it. -- Stephen Vizinczey


Daarken
Rara Avises
Premium
join:2005-01-12
Southwest LA
kudos:3
Now that is a useful reply that can definitely help the OP.
--
Getting it Done.


Duramax08
To The Moon
Premium
join:2008-08-03
San Antonio, TX
reply to LLigetfa
said by LLigetfa:

The OP has not provided enough useful information. All we know is the old house had a mast. There is mention of "25 feet in the air" but we don't know if that is the old house or the new house.

The height is relative to the terrain and the trees in relation to the tower, all of which are a mystery. We don't know anything about the house construction, roof style or height, etc.

Then there are concerns about lightning protection, cable lengths and runs, etc.

One needs to start with a site survey to ascertain just how high it needs to go and then take it from there.

I already have a "mast" with a antenna on it. works just fine. Since its about solid steel and we had a hard time raising it up, id rather build my own. And I also said

" I was planning not to bring my antenna over to the new house (about 25 feet in the air)"

I just want to know how to build one, simple as that.


Daarken
Rara Avises
Premium
join:2005-01-12
Southwest LA
kudos:3
I ran across this via google.
"WARNING
Make sure that this metal antenna support cannot come in contact with overhead power lines during tilting or at full height. Consult your local zoning authority for any restrictions in your area. Call your local "Miss Utility" prior to digging if there is any doubt about the location of underground utilities. Neither the author, nor your editor, nor CADX make any representation regarding the structural soundness of this design nor have we tested the design to determine the ultimate load-bearing capability.

The mast is made out of 1¼ inch rigid steel electrical conduit, (one could use even heavier conduit if desired such as 1-1/2 inch or even 2 inch) . The conduit comes with threaded couplings that allow two or more pieces to be joined together. The mast itself is made from two ten-foot lengths and one five-foot length of the conduit screwed together end to end. Two more ten-foot lengths are partially buried in the ground and are used to serve as the mounting base for the mast.

To begin the installation I used a post-hole digger to dig a four-foot deep hole. Prior to setting the pipes in the ground, I drilled two holes in each of them at a point that would be about three inches above ground level once the pipes were set in the ground. These holes, as well as 2 holes in the bottom of the 25-foot mast would all line up and serve as the pivot point so the mast could be tilted over.

I then put two ten-foot lengths of the conduit in the hole with 6 feet of each pipe protruding above ground level. These two pipes were set in the ground side by side with about two inches of space between them to allow for the 25-foot mast. They serve as the base that holds up the 25 foot mast.

After carefully checking the pipes to make sure they were perfectly plumb (i.e. vertical), I filled up the hole with four sixty-pound bags of concrete mix. This gives the mast a very solid base. Once the concrete has set, the mast was ready to be erected.

I inserted an 8-inch long by ½ inch diameter bolt through the holes for the pivot point. I also drilled two holes in each ground-mounted pipe at a point about three inches from the top of each pipe. I then drilled two holes in the 25-foot mast at a point which would line up with these holes at the top of each ground mounted pipe once the 25 foot mast was tilted up to it's fully erected position.

I inserted another 8 inch long by ½ inch diameter bolt through these holes to hold the mast in the erect position.

I took advantage of the base mount pipes being threaded on the ends and screwed caps on them to keep the weather out. Even the very top of the mast where the 5 foot section of pipe is, I had that threaded at the hardware store so I could screw a cap on it to keep the weather out.

To mount the Alpha Delta Sloper antenna itself to the mast, I drilled two holes at a point about three inches from the top of the mast and inserted a stainless steel eye bolt so I would have something to hook the antenna to. All bolts, nuts, and washers are galvanized and/or stainless steel to ensure long life without rusting.

I also used clear silicone sealant at all points where holes were drilled to seal out the weather.

All that was needed to secure the coax cable as it traveled from the antenna down the mast was some plastic, UV resistant, cable ties that are available at Radio Shack. These cable ties made it a very neat looking installation. I wrapped a cable tie about every 12 inches around the mast to secure the coax cable to the mast. One could use electrical tape to wrap around the mast to secure the coax cable as it travels down the mast but the tape would eventually come loose and start flapping in the wind.

Now when I want to tilt the mast down to work on the antenna all I have to do is remove the top bolt that is at the approximate 6 foot level, and walk the mast down to the ground. Simple and safe!

I would recommend that you use only a lighter-weight wire type antenna on this mast because the antenna will exert a pulling force on the mast in only one direction since there are no guy wires pulling in the opposing direction. Too much of a pulling force (weight) could cause the couplings that connect the 10 foot pipes end to end to become weakened and possibly break. A home made end fed long wire antenna or dipole antenna should not be too heavy as long as the antenna is not extremely long and not made out of too heavy a gauge of wire. You could even erect 2 of these masts, one at each end of the antenna. The Alpha Delta Sloper is a somewhat heavier antenna than a plain long wire or dipole because it has large coils in it so I am a bit more concerned about the mast than I would be with a lighter weight plain end fed wire or dipole antenna mounted on it. So far my mast with the Alpha Delta Sloper on it has been subjected to 50+ MPH winds and held up fine. I suppose that since the Alpha Delta Sloper has held up fine that an Eavesdropper Sloper and other similar antennas would also work well.

I bought all the necessary parts for this project at the local Menards Home Center and Radio Shack. The total cost was just under $100. That might seem like a bit much for a 25-foot mast but it sure beats the danger of standing near the edge of the roof and struggling with the old set up, especially in winter. It looks so much neater too, especially since there are no guy wires. It is also much cheaper than a commercially available 25-foot free standing tower or crank up mast which would cost hundreds of dollars.

A sketch of the mast is available by sending me an e-mail message requesting it. I will send you a jpeg format file with the detailed sketch.

Here is the parts list:

5 - 10 foot x 1-1/4 inch diameter rigid steel electrical conduit pipes
4 - 1-1/4 inch caps to screw on the ends of the pipe
4 - 60 pound bags of concrete mix available at any home center or hardware store
2 - 8 inch x ½ inch diameter galvanized bolts
4 - galvanized washers to fit the ½ inch diameter bolts
2 - galvanized nuts to fit the ½ inch diameter bolts
1 - stainless steel 4 inch x 3/8 inch diameter eye bolt with 2 nuts and 2 washers
1 - tube of clear silicone sealant/caulk
1 - package of cable ties from Radio Shack"

»home.earthlink.net/~dxchicago/fr···ding.htm
--
Getting it Done.


WHT

join:2010-03-26
Rosston, TX
kudos:5
reply to Daarken
said by Daarken:

So instead of pointing out the obvious flaws of my installation, why don't you provide the OP assistance with his question.

I did provide assistance. 15 feet of USB won't work. A long coax run needs low loss coax.
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Maniak

join:2008-03-29
Vail, AZ
Reviews:
·Wi-Power
·RuralNet
reply to Duramax08

Re: How to build a antenna pole or (mast)

Click for full size
Mast with 1.9ghz antenna and wi-ex cell booster antenna

Mast with 5.8ghz WISP antenna, 1.9 ghz grid and wi-ex antenna
I used two 10 ft sections of black gas pipe with a coupler between them. The bottom is burried 2 feet into the ground and I put a 2x4 on the facia (to get it connected to multiple rafters) and used a piece of strap steel bent over the pipe to hold it to the 2x4. I put a single self tapping screw through the metal strap into the pipe to keep it from rotating.

It has been up for upwards of 3 years now and has seen winds over 60mph.

So far so good.. no lightning strikes on it but I do have lightning arrestors on both lines coming into the house (one is cat 5, one is lnr240).

The 2nd pic is when we had all of the antennas on the mast, and I still had an external CCD camera wire still on there (camera was off). I have since removed the wi-ex anenna and the grid antenna is not being used but is still there. Even in high winds with the WISP (diamond) and the 1.9 ghz grid there is very little movement.

~Mark


Duramax08
To The Moon
Premium
join:2008-08-03
San Antonio, TX
Neat! I used half inch conduit with couplers going about 20 feet in the air. We had some grounding stake made of copper laying around and hammered that about 2 feet in the ground. We put the conduit pipe over it and strapped the top to the house. It works ok, the conduit is leaning a bit but guess we'll see how long that last :P.
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