Portable PVC Conduit Antenna Mast

Intro: Portable PVC Conduit Antenna Mast

Build this portable antenna mast for use in temporary or emergency communications. Possible applications include setting up temporary wifi for an event or as part of a portable emergency communications station for Amatuer Radio Emergency Services (ARES).

STEP 1: Supplies

(3) 10' x 1 1/4" PVC conduit
(2) 1 1/4" PVC caps
(3) Screw anchors
(3) Eye bolts
100' x 3/16" nylon rope
Landscape timber spike

STEP 2: Cut Conduit Into Portable Sections

Cut each length of conduit in half to make 5 foot sections. Five feet sections fit nicely in the trunk of my car. Adjust the dimensions to suit your needs.

PVC conduit has one flared end which works well for this project. The flared end should be at the bottom of each section in order to keep water out of the mast in wet weather. The very bottom section is made from a piece of PVC with no flare. The total length of this mast is 20 feet. It could be made taller by cementing a PVC coupling or matching threaded ends. If you go taller you may wish to add another set of eye bolts and guy ropes.

STEP 3: Insert Eye Bolts for Guying

Measure up about 18 inches from the flared end of one section and drill 3 holes through the center of this section. Space the holes about an inch apart and rotate the conduit with each hole so the eye bolts will be approximately 120 degrees apart (measure the circumference and divide by 3). Insert the eye bolts and tighten the nuts.

I plan to run coax up through the center of the conduit so I also cut a slot in the bottom of the base section where the coax will exit.

This would also be a good time to number each section. The top 3 sections each have one flared end. The top section being number 1. The second section , with the eye bolts, number 2. The third section with a flared end, number 3. The bottom section with no flared end, number 4.

STEP 4: Guy Rope

Cut the 100' rope into 3 equal lengths. Tie one end of each rope to each of the eye bolts.

STEP 5: Base Anchor

You'll want to keep the base of the mast from moving. I expect to use my portable mast primarily in grassy areas so I've chosen to use a timber spike and a PVC cap to hold the bottom of the mast firmly in place. Drill a half inch hole through the end cap. Choose where you want the mast to stand and push or pound the spike into the ground through the cap.

STEP 6: Screw in the Anchors

The anchors should be approximately 120 degrees apart and about 15 feet from the base. Start from the base and walk off the distance to each anchor location and screw it into the ground. Tie a tautline hitch with the loose end of each rope to each of the anchors. The tautline hitch is a knot that will allow you to make adjustments in each guy rope to hold the mast perfectly vertical.

STEP 7: Attach the Antenna and Raise the Mast

I made this simple antenna for the amateur radio 2 meter band and afixed it to an end cap. Thread the coax through each section starting at the bottom and then attach it to the antenna. Set the antenna on the top section and assemble the sections from top to bottom while raising the mast vertically. Hold the mast in place while a helper takes up slack in the guy ropes.

(Note: I had to remove one of the eye bolts in order to thread the coax through that section.)

Comments

[kilo5]

A PVC mast is a fun hobby project, but for frequent portable use I'd recommend a telescoping fiberglass mast instead. PVC is pretty flexible, to the point where a length more than about 20 feet can bend over into the shape of a rainbow, and immediately fall apart at the joints. Also if the mast falls over and hits the ground, the pipe will usually break.

[cybork18]

I totally agree. The described can be done, tried that myself, bur for emergency use you probably need something reliable rather than experimental. In emergencies you certainly want to cope with that case, and not have more worries due to a flexing and falling mast?
Insight from trying similar construction is that the mast bends away easily from being straight below the guying hooks, and once bent from bejng totally straight, the weight pushing from the top bends ghe mast even more to the same direction. E.g. in case of wind load, froce from one side translates into even more pressure downward by translation of the guyjng, and that makes the whole setup collapse quite quickly.
Not yet speaking of ghe intended top load (antenna).
Putting up such a mast with top load attached is difficult as well...
Very good jnstructable anyway, lots of things to learn about mechanical forces!
73!

[jhalsey52]

If you want I suggest down sizing length to 6ft for back yard use apartments has strict rules for antennas masts placements ok.

[Grimling]

Hay , Where i live , there isn't cable tv , so we have to do it with those old antennas , but all our antennas really suck ... , i was wondering if anyone knows of with kind of iron the antennas are made , so i can get one and make our somewhat bigger and better :p , are there other things i must look at with this project ? Thx , A dude who lives to far away .

[twighahn]

Aluminum

[j79jon]

Hi..I am a Ham WB5NWT but for a Diy good TV antenna and I am useing them ...Google SINGLE GRAY HOVERMAN...and go from there...I have built almost all of the Hoverman antennas and they are ffrom 6dbi up to something like 16 dbi.

I use # 8 wire for the antenna elements. Put one end in a vice and with drill twist the wire until it gets stiff. Easy to build.

73s & GL..John SE Texas

[radiorental]

Aluminium, if you're bored and you're in to computers I HIGHLY recommend searching youtube for 'IT Crowd' a ferkin hilarious show from the UK.

[Countryboy7239]

Youtube.com has a lot of interesting shows, especially old ones. The problem is, they're all in ten minute sections. Hulu.com has some really good movies on it. Plus you could always subscribe to Netflix and just order movies.

[static]

Well you should be thinking antenna "system" and maybe that is what you are thinking. A quality antenna, a rotator if desired stations are wide spread on the compass at your location. Quality feed live. An amplifier, placed at the antenna end of the feed line. Antennas are made out of aluminium. If the plan is to build hannel specific yagis you may save, but otherwise you may be better off buying an off the shelf log VHF periodic/UHF corner reflector antenna. Make sure all connections are terminated with a TV or a 75 terminating resistor. In the end the sad fact may be you may to far into the fringe.

[RedSevenOne]

Aluminum is your best bet, If you have a a local HVAC contractor around you might find him/her friendly enough to 'tour' the scrap pile. in their yard.

[theprofessor]

bigger would do you no good, the longer the driven element, the lower the frequency at which it resonates, most TV is vhf/uhf so smaller antenna, it is possible to get an antenna with more 'gain' however this number is misleading with antenna, your best solution is to get your existing antenna higher in the air.

[imarunner2]

For a directional antenna, like most TV antennas, you'd probably want to come up with a way to guy the mast in such a way that would allow you to turn the antenna for best reception. Perhaps a ring large enough to slip over the small part of the mast yet small enough to not slip over the flared end. Then you may have a problem keeping it from turning in the wind...hmmm.

[PaulE2]

Will get better results using schedule 80 pvc pipe - it doesnt flex as much as the schedule 40 shown here.

[tomreedtoon]

I'm trying to put up a small TV antenna (with rotator) on a house. The roof is so bad that other alternatives (like an old DirecTV dish mount or attaching a mast to the chimney) is impossible. As a cheap alternative to buying a pro mast, I was thinking of using two chain-link-fence top rails, 10 feet long each, to make a 20 foot mast, putting the bottom end in concrete, then bolting the top to the edge of the roof with a brace. These top rails have a "swedged end" so they fit into each other, which I'd probably reinforce with some kind of bolt-on metal collar.

Does this sound reasonable to you guys? This is the URL for the top rail I was thinking of using:

http://www.homedepot.com/h_d1/N-5yc1v/R-100322532/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053

[Dr.Bill]

KB1LZL asks; Are you a Ham?

[imarunner2]

Yes. KB9LNS

[maccafromoz]

Self contained mast. Get a length of water pipe fit a rotor at the top/one end of the pipe have a square plate welded to the pie just below the rotor with four holes to pass wire rope through hold wire ropes secure with wire rope clamps the suit your rope. half way down the length of pipe weld another larger square steel plate oriented the same as the top one put a groove where the wire rope passe at each rope. Weld another fixed square plate at the bottom fitting a shackle to the rope holes with a turn buckle loop the rope from the top of the mast through the turnbuckle hook and fasten the wire rope with clamps to suit make sure all clamps are tight then tension each cable evenly and your mast will not bend or buckle, no matter what the diameter you choose. anchor the pipe at the bottom or a place where it will not topple

[Wyle_E]

If you're using four five-foot sections, you only need two ten-foot sections plus a coupling to add a socket to one of the five-footers. Of course, PVC tubing is so handy that that you'll probably find a use for that last five feet. You could, for instance, split a short length lengthwise to reinforce the section that you drill for the eyebolts.

[cheordinario]

nice. i`d like to build the 2 meteres antenna you have on the top. can you post an instructable for the antenna?

[wperry1]

This is a great instructable. I wonder if you couldn't get around the problem of having to remove the eye bolts by attaching something around the outside of the pipe rather than screwing into it like a u-bolt or hose clamp.