Creating Antenna Masts Using Chain Link Fence “Top Rail”

Lew French, KCØUER, gave me this idea. Components for chain link fencing are inexpensive. The so-called “top rail” is the horizontal runner across the top. Lew showed me how one end on each is tapered to fit into the next pole. One pole atop another is sturdy enough for about a 22-foot mast. I said “aha!” and realized I had a solution for raising my 80-meter full-wavelength horizontal loop antenna a little further off the ground. Right now it’s held in place by ropes thrown over trees. So, I’m replacing the current antenna (made out of old army-surplus field wire) with something stronger. Here’s a picture of how I attached things to the top of the antenna.

Mounting hardware atop mast

Mounting hardware atop mast. The mast is chain-link fence “top rail.” Note the pulley to raise and lower the actual antenna.


Okay, so here’s the deal. I wanted a sturdier antenna. I wanted it to be longer (tuning the current one on the bottom of 80m is problematic). I wanted it to handle full legal power should I ever get an amplifier. And, I wanted it to be cheap. Really cheap. And I wanted it to be easy.
Pulley atop mast

I attached the pulley to the top of the mast using a sturdy hose clamp. Note that the “extra” hose clamp is bent out of the way so it won’t abrade the guys. Then I tied the guy ropes to the pulley’s ring.


The problem with a horizontal loop is that it needs four supports, one for each corner. The first support is easy—it’s atop my house. But to get any kind of decent supports for the other three corners seemed to be an impossibly expensive option—towers aren’t cheap, even small ones. But with the inexpensive top rail, my problems were solved. Now…one top rail inserted into another is a wobbly thing. I tried three, but that was way too wobbly and would have required guying both in the middle and at the top. So I compromised on two, giving me about 23 or 24 feet of height. Each “tower” has a pulley at the top to raise and lower the actual antenna, plus each has three guys which are actually polypropylene cord. (My wife doesn’t care for the colors—rather bright, but that’s all I could find at Home Depot.) I tied the top end of each guy to the pulley’s ring, which is smooth, to reduce the probability of wear, plus it’s firmly in place. So, the complete “tower” (mast) assembly is two top poles, one inserted into another, with the joint taped with duct tape. The tape is only important during mast erection—in normal use things are held in place by gravity, but the two poles showed an annoying tendency to separate during erection. I spread the guys out on the ground, then walked the antenna upright.
Antenna corner masts hidden in the trees

The poles are raised so that they’re in between the trees and the loop can run from one mast to the next without getting tangled in tree branches. Each mast has a pulley to facilitate raising the actual antenna, an 80-meter full-wavelength horizontal loop.


While my wife, Loretta, KBØVWW, held the pole upright, I tied the guys to nearby trees. My goal was to tie them high enough on a tree that no one could walk into one unawares, and low enough that high winds wouldn’t cause that part of the tree to sway back and forth. I was able to meet both those criteria with all the guys. One had to be stretched quite far to ensure it was high enough above the driveway that the propane truck can drive underneath without a problem. We did final checks to ensure the masts were vertical by moving the base—not the top—figuring that was much easier than constantly adjusting guys. The poly cord has quite a bit of stretch, so I figure they’ll stay in place in a windstorm.

I’d very carefully sited the masts so that the antenna wire can run without interference from the trees—a nice line of sight from one mast to the next. And, from the front of the house, the masts are nicely hidden from view, as you can see in the photo. The next step is to string the antenna itself. That will be the subject of another post.

(You may say to yourself that this new setup doesn’t look terribly permanent. Well, it’ll stay up for a few years at least, and by then I’ll want to change everything anyway!)

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19 Responses to Creating Antenna Masts Using Chain Link Fence “Top Rail”

  1. Mike / N4ZN says:

    If you want to trade a little money for MUCH easier installation, and have a single piece install that’s easily moved, here are two solutions:

    23′ lightweight- https://www.homedepot.com/p/Mr-Longarm-Pro-Lok-23-ft-Adjustable-3-Section-Extension-Pole-2324/100177392

    30′ heavy (or heavier weight)-https://www.homedepot.com/p/DocaPole-7-ft-30-ft-Extension-Pole-Multi-Purpose-Telescopic-Pole-for-Window-Cleaning-Gutter-Cleaning-and-Hanging-Lights-DocaPole-30/314617947

    These both eliminate the need to “walk it up”, with the use of a short ladder, and are easily erected in minutes, also making them ideal for portable use, as well.

  2. dcasler says:

    Be sure to guy it very thoroughly. Personally, I don’t put more than two of them together. I think three are too wobbly.

  3. Matt says:

    I am going to be using top rails as well cheap easiest for me to mount my j pole antena
    Or 5/8 antenna. They are not heavy antennas.
    I want to bracket it to the side of my house or or on
    Top of roof, but I wanna add 40-50 foot 4-5 sections.
    Does pl premium work to seal the sections from wobbling?
    Please comment and let me know the best way.

    Thanks

  4. David Oswald says:

    I’ve used this idea for my mesh system. I’ve had a 24 dpi grill antenna with a ubiquiti bullet m-2 on a 30 foot mast. It’s been up for 5 years, but bent in a heavy wind at the base last Sunday evening, 3 May 2020. I’ll be getting a few more poles at next opportunity to get the set up back in the air.

    73
    David Oswald
    KD7DHO

  5. den @KC3BCP says:

    Hi,
    Great idea but I’m concerned about lightning. Can anyone recommend a solution to this problem ??

  6. Danny says:

    Although this is a lot later – my idea is still sound.

    Use self tapping S/S screws in the joints. 3 would work fine.

    If Joint is UP then rain water will seep into the joint and down the pole. Drill or notch the bottom to let water out and also let it “breath”.

    If not water will pool up inside

    If joint is down, then water won’t be able to go UP.

  7. Antenna Man says:

    I’m thinking a pluming repair clamp might work well to stiffen between sections. The bolts will make it very tight and it’s galvanized and light weight.

  8. dcasler says:

    The poles are temporary, so I haven’t installed ground rods for them. My “permanent” HF9V Butternut is well-grounded.

  9. Jeff KN4NIQ says:

    Dave what about lightning protection? Do you have it for your poles?

  10. dcasler says:

    My antennas are on metal masts too. I once modeled the mast as part of the antenna and found it made little difference–some, but not much.

  11. Matthew says:

    This seems almost too simple. I’m pretty new to Amateur Radio and find it curious all the notes and comments I see about the disruptive effects of conductors within the vicinity of an antenna when I can look out my window and every commercial VHF antenna I see is mounted to a metal mast. How much effect does using fence top rail influence the radiation pattern of a vertical mounted to it?

    Matthew
    KE8KAO

  12. Grant S says:

    This weekend I plan to install a 30′ tower atop my 20″ roof peak. I am using three top rails and applying PL Premium to each joint, hopefully eliminating wobbling. To ensure that it cures straight while laying on my uneven floor, I plan to put a small light at one end, then cedar-shim the assemblage here and there while gazing through the opposite end to see if the light is centered in the tube. Once it looks straight I will leave it for a day or so.

    On the top end I will be installing a rain cap, on the bottom end the “Galvanized Chain Link Fence Rail-End Assembly (SKU 1000424634 at Canada Home Depot)”, with PL Premium to seal and eliminate movement. This fixture will function as a hinge, allowing me to tip the mast up and down as required. My base will get a very heavy copper cable leading to a ground plate for lightning protection.

    Guy wires will be placed at the 13 ft and 26 ft points, leaving an ample 4 ft area free for affixing antennae with muffler clamps. The guy wires will be held at each corner of my house with a 3/8 x 1-1/2″ lag eye bolt. Since it is almost December, I feel like I might as well add Christmas lights to the guy wires, and a star up top made from a string of chasers. This will make it very easy to figure out where I have a line of sight 🙂

    Will comment again after completion with a link to some photos. Cheers!

  13. Russ Harmon KC7WVQ. says:

    Put a cap on the top of the mast to keep rain out. I used silicone adhesive to make it a water proof. I painted mine flat black and they almost disapear in the open. To stiffen the mast even more use 3/4 angle iron and either weld it or use gear clamps to hold in place.

  14. Herb says:

    I used this idea in 2011 to put up a dipole. I used a hack saw to cut a slot in the larger diameter end of the upper rail, put the two rails together and used a muffler clamp to hold the two rails together. My antenna mast has been up for almost 7 years and has withstood winds up to 70 mph. This is a great way to put up a low cost antenna mast.

  15. Mike says:

    Have you thought of a telescoping flagpole? A telescoping flagpole is aluminum to avoid rust and each section probably will twist lock in place. Although, mine are bolted in place to avoid failure. With or without our flag, it’s quit sturdy. The halyard to raise and lower comes in handy for routine maintenance. Mine mounts two halyards for a G5RV for HF bands @ 35 feet along with a J-Pole for 2 meter / 70 centimeters. Remember, in lightning conditions disconnect your coax from your home and radios.

  16. K1RSU says:

    Chain link fence pipe comes in 4 different ODs, in 24 foot lengths

    check with your local chain link materials supplier…

    1-3/8, 1-5/8, and two more sizes with larger ODs

    they will deliver…

  17. Marty Paulson says:

    If you use inch and 3/8 brace bands on the joints they will stiffen up considerably especially if you use the heavy duty type which I found on Amazon, amazingly. I’m using 2 top rails on a 40 Meter dipole and it works well with 120′ open ladder line, at least for me being a 6 month old ham.

    Cheers,
    K7CMI
    Marty

  18. James S says:

    Both these ideas are good working ideas for a cheap mast. One thing that wasn’t thought of was that any sideways movement will have a tendency to wallow the major ID out allowing the upper piece to start sliding down over the lower piece. To counter that action and as an additional safety, place a stainless steel hose clamp at the bottom of the upper section. It wasn’t mentioned, but the bottom section of mast should have the swagger end up. This also keeps water from getting into the mast at this joint.

  19. Richard E Jubinville says:

    This is a very inexpensive yet very effective idea Dave!! I have another thought to give you more height and a sturdy base should you need it. It is something that I may need to do if I want to run my Windham E-W, and that is to use a 12 foot PT 4×4 post that you can buy at HD or Lowes etc. set into the ground about 3 feet. Then, use either your fence rails or use TV antenna 10 foot mast/s and mount the lower one to the top section of the 4X4. I have two trees that are in perfect alignment to run 265 feet so that I can cover 160 meters through 2 meters, but my direction is SE to NW. If I ever decide to run SW-NE, I do not have trees at both ends, so I will need to use an idea such as yours at at least one end. Good idea Dave,
    73 Dick
    KA1VEI

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