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Putting an Antenna Support System in Public Trees

Created by Arno Dienhart, K7RNO on 2019-09-28

"Editor's Note: Due to the popularity of some of eHam's older articles, many of which you may not have read, the eHam.net team has decided to rerun some of the best articles that we have received since eHam's inception. These articles will be reprinted to add to the quality of eHam's content and in a show of appreciation to the authors of these articles." This article was originally published on: 10/02/2013





Putting an Antenna Support System in Public Trees

I am limited to public places with tall trees to put up anything at a decent height. My favorite is a nearby State Park (Utah Lake SP). I also have a favorite tree there. The time to shoot up a line, to pull up a twine, to pull up the antenna, is stealing air time and is often a hassle when the shot doesn't go where I want it or the line gets entangled in the tree. So, the solution is to install a semi-permanent system of lines and a block (the proper name for a pulley) to stay in the tree and allow me to just go, attach my antenna, pull it up, fan out the radials or the dipole legs and be on air. To make this legit, I asked the Park Ranger for permission, which he easily granted (declining any liability, of course).

This is about how I did it. Because I appreciate detailed, unambiguous instructions for myself, I will also give a detailed write up. Bear with me.

Materials needed:

A block. Either around $30 from a boat supply source, or $3 at the hardware store (I prefer the larger-wheel type, like for a clothes line, over the smaller Chinese crap).

200-300' of line in one uninterrupted length. Depending on how far into eternity you are planning, you may want to invest in UV-resistant line. DX Engineering sells a black 1/8" one on a 1000' spool for $72. I used camo decoy line from the hunting store (1/8" thick, 250', $12). Don't use anything bright or you risk curious children to explore why that line is there. You want to hide this!

Around 150' of twine for the intermediate step, unless you are confident that you can get your thicker line up with the thin monofilament. For twine, a mason line works great.

That's it for materials. It will help if you have (or can borrow) something to shoot up that first line, but you should already have something that worked for you in the past. I had modified a slingshot by attaching a fishing reel with 10# monofilament and a 1 1/2oz lead weight. Total cost around $25.

Setting it up:

At the end of this procedure you will have one stationary line tied in the tree holding the block (the block line) and one loop of lines from the block to the ground, the antenna haul line.

1. Identify your tree and your branch. Consider one that leaves sufficient open space to spread out an inverted V or elevated radials, if you will use those.

2. Shoot the monofilament into the tree and over your branch where you want your antenna to go up. If you missed it, don't settle for second best. Reel it back in and shoot again until you are satisfied.

3. Hope for the best that the weight comes down not too far from where it went over the branch. Aiming steeply, almost 90° up, will help.

4. Remove the weight and attach the twine. Pull the twine up over your branch and down to the launch spot. If you don't want to use the intermediate twine but the final line right there, skip step 5, but read it to understand the progress and learn the tips regarding entanglement.

5. Attach your final line to the twine and pull that over your branch and down, pulling ALL of your line to the down spot, making sure you don't pull up its end as well and lose it (attach it to a tent stake to prevent this). To prevent later entanglement, drop each haul into a large flat box. When done, pull the end out of the box, hold it in your hand, and turn the box upside down to drop the heap on the ground bottom up. Now you have the end of it accessible on top of the heap, which is where you want it for step 7.

6. Attach your block to the other end of your line, over the launch spot. A bowline knot is a good one for that.

7. Now grab the end of the line from the heap and walk it to where your block is hanging. Feed it through the block and tie off the end to the ground (tent stake or weight). Make sure the line runs in the groove of your block and will not get squeezed in between.

8. Start pulling up the block with the fed line hanging down from it and make a new heap of line as you pull. The block will go up, with two strands of line hanging down from it. Pull it up all the way to the top but make sure it won't slip over your branch. You don't want to waste height by not pulling it up high enough. If in doubt, bring your binoculars to check where the block is (or have a second set of eyes assist you). Once you have it where you want it, secure the block line temporarily and pull on the double antenna haul line, making sure it runs smoothly over the block. If not, it may have twisted or squeezed in the block. Untwist the two strands or lower the block again to fix it if necessary.

9. Find a branch on the trunk high enough for you to just reach (I use a chair for this to stand on --the chair I will later be using to sit on when I'm hamming). Cut the block line at a length that is long enough to tie it securely to that binding post. Make sure it is hidden well. Done with the block line.

10. Cut the antenna haul line to a length that gives you a loop, which almost reaches the ground. Attach a hook of some sort to later attach to your antenna, and to close a complete loop for when you hide it in the tree.

11. Feed the antenna haul line into the branches as well as you can so it is hidden from exploring eyes. Tie the end of it where you can, again up high enough to be hidden and hard to reach for kids.

That's it. Have fun.

UPDATE: By now I am working with the third iteration, because of my own disregard of some of the suggestions above. Particularly the ones that talk about securing the haul line. When I proudly demonstrated the first antenna hoist to my wife I forgot to secure the loose end of the loop. When the weight of the antenna pulled the loose end up, it was lost, went over the block and came down to the ground. Now the block was useless and, to get it back down, I had to yank so hard that I broke off a branch the size of 1 ¼" thick.

Not enough, though. Today, I went back to set up a new support system. With the haul line now already cut to proper length, it was shorter than the first time, where I had most of the 250' available and only had to secure one end of it. So today, I followed my own advice and secured one end of it. Duh. I forgot the other, now short end, and when I hoisted up the block, that loose end went up over it and came down again happily. Arrgh!

Now it is up again properly but my stronger branch being gone, it is now running over a rather thin branch and I have yet to see how that will budge under the weight of a full antenna setup. Live and learn! I'm getting better at shooting lines up, though. Ha!

KB2FCV 2019-10-02
RE: Putting an Antenna Support System in Public Trees
Most parks here have a "leave it as you found it" policy, not allowing anything like this.. but I suppose if you have a favorite spot, there is nothing to lose by asking.

When I take my QRP stuff to the park, I use a simple end-fed antenna and I use some mason's twine and a 1/2 filled water bottle as a weight to get the line over a branch. It's fast, easy and safe. I'm usually just looking to make a handful of contacts for a couple of hours.

That is great that the OP was able to obtain permission from their preferred park for a semi-permanent setup. My home dipole / tree setup isn't even as elaborate.
WB2GMK 2019-10-02
Putting an Antenna Support System in Public Trees
I am planning to take a cruise from Tampa, to NYC and thence to some port in Spain. I hope to obtain permission to operate on the high seas from the master of the ship and the radio officer. I have been told this is nearly impossible to obtain, these days. I don't know why, since almost all high seas communication is via satellite radio, but I will give it the old ham-radio-effort. I hope to be able to toss a wire out the pothole of my cabin and fire up the 10 watt Elecraft. Any advice would be appreciated. Ping me at WB2GMK@arrl.net or actin.biz@gmail.com

Thanks es 73
Greg WB2GMK
WB2GMK 2019-10-02
Putting an Antenna Support System in Public Trees
I am planning to take a cruise from Tampa, to NYC and thence to some port in Spain. I hope to obtain permission to operate on the high seas from the master of the ship and the radio officer. I have been told this is nearly impossible to obtain, these days. I don't know why, since almost all high seas communication is via satellite radio, but I will give it the old ham-radio-effort. I hope to be able to toss a wire out the pothole of my cabin and fire up the 10 watt Elecraft. Any advice would be appreciated. Ping me at WB2GMK@arrl.net or actin.biz@gmail.com

Thanks es 73
Greg WB2GMK
WB0OEW 2019-09-30
Putting an Antenna Support System in Public Trees
I am amazed any park would allow this.
AG5UP 2019-09-28
RE: Putting an Antenna Support System in Public Trees
Yup, that dog lead should help with the bark, all right!
W4FID 2019-09-28
Putting an Antenna Support System in Public Trees
I use a "dog lead" made from fairly light gage stainless cable and plastic covered (from Home Depot, Pets Smart, Lowes) for a few feet where the block line goes over the branch so the tree bark doesn't wear thru the cloth line.