How We Flew An End-Fed Half Wave (EFHW) Ham Radio Antenna On A Kite (VIDEO)

I’ve developed a bit of a kite fetish. Some time back in July I learned that people flew antennas on kites. One of those people was Guglielmo Marconi whose kite antenna enabled the first transatlantic wireless communication. As someone who tends to always gaze toward the future, my interest however was decidedly not inspired by the past. Rather the whimsical fantastical vision of a wire dancing across the sky sequestered my imagination. I began to gather supplies.

I learned that the diamond-shaped kites of my childhood were not actually the correct choice for this effort. If you want to lift objects, the sled kites or parafoil kites are your best bet. Parafoil kites are like modern-day parachutes. They have no rigid components and rely on air flow to fill up “cells” in order to provide lift. Sled kites on the other hand have a mixture of a semi-rigid frame and air cells. I wanted a parafoil kite because I could ball it up and throw it in my backpack. Instead, due to supply chain issues (yes, kites are affected too!), I wound up with the Cubic Power Sled 24 from Into The Wind. What an impressive kite!

The “24” of the Cubic Power Sled 24 actually refers to its area. The kite dimensions are about 8 feet x 3.5 feet. Quite frankly, I could not fathom a kite that large when I ordered it. The entire kite wraps up around itself, folds in half, and can be stored in its drogue (i.e., the tail that hangs off the back of the kite) which doubles as a bag. The only necessary accessories were 500 feet of 300 pound test dacron kite line and 9″ hoop spool. I also bought an anemometer to measure wind speed for the heck of it. You can see one of my first successful flights (without an antenna) of the Power Sled here.

So what antenna was I going to send up this kite? Most ham radio references to kite antennas used a random wire. I purchased a MFJ-16010 Random Wire Tuner and an LDG RU 1:1 unun. I took a literally random length of 14 gauge house wire and attached a banana plug to be shoved into the antenna port of the tuner. You can read more about my efforts with this here and here. The goal was that the radiator would fly up on the kite string while attached to the tuner whose chassis would be grounded into a ground stake. The tuner would then be attached to a 25 foot length of coax, then the 1:1 unun, and then another 25 foot length of coax back to the transceiver. While extremely interesting to me, this was not ultimately the antenna that made it up the kite.

Still with the random wire in mind, a friend suggested fishing leader wire as a possible radiator. I also bought some fishing tackle crane swivels to hold the wire onto the kite line.

My impression was that this was a precarious and tedious arrangement. Regardless, we never had a chance to test this set up because of a simple lack of wind. That is AA1F below at Ward Hill Reservation in Andover MA patiently awaiting a gust.

While my interest in the kite antenna never waned, the coinciding of my availability and a windy day never seemed to occur. One day during another radio adventure, I ran into a couple flying kites in a beachside parking lot. This was just the inspiration I needed to renew my high-flying antenna efforts. In fact, in watching the techniques of this experienced duo, I realized I was overthinking things. There was no need to use a random wire on the kite. Just send up the radiator of an end-fed antenna and leave the unun on the ground. My homemade 49:1 EFWH with a 60′ wire (cut for 40M) would do just fine! On our next windy free day, AA1F and I went to Pope John Paul II Park in Boston MA (POTA reference K-8422) to finally get the kite antenna on the air!

Here’s how we did it. I want to point out that we DID NOT GROUND this antenna. I have heard that antenna wires flying on kites can generate a tremendous amount of static electricity that can be harmful to both the radio equipment and the operators. While we did not seem to experience any trouble with this, it is probably best to adopt a system that bleeds off the static. Regardless, if you refer to the above diagram along with the pictures, you can see how we got our kite antenna on the air.

First of all, we picked a very open field free from utility poles, trees, or other hazards. We identified a spot where we wanted to operate, laid down a tarp, and set up the radio (complete with autotuner and battery).

Next, a cinderblock was positioned approximately 20 feet away from the operation tarp. Two separate loops of paracord were tied around each cavity of the cinderblock to create separate anchors for the 49:1 antenna unun and the kite line. The unun was tied directly to one of the cinderblock paracord anchors, and 25 feet of RG8X coax joined it to the LDG Z-100 Plus tuner on the tarp. The tuner was connected via a short jumper cable to the Yaesu FT-891A transceiver.

The kite was positioned approximately one hundred feet downwind (on the ground for the time being) from the cinderblock. The kite line was unraveled back to the cinderblock. A loop was tied in the kite line and this was attached to the other paracord anchor via a carabiner.

The 60 foot radiator wire was rolled out next to the kite line which was simply laying on the ground at this point. The free end of the radiator wire was simply tied in a simple loop. A cable tie was looped through the radiator wire loop forming an end insulator and attachment point.

After the radiator wire was rolled out, a carabiner was secured on the adjacent area of the kite line. The method for securing a carabiner to a kite line is simple and effective: simply wrap the kite line three times around the shaft of the carabiner. The cable tie loop of the antenna wire was now secured onto the carabiner as well.

Working my way back from the attachment point at the end of the antenna wire toward the unun at the cinderblock, I added a few more carabiners to the kite line at approximately one third and two thirds the length of the antenna wire. I simply fed the antenna wire through the carabiner gate. This would allow the antenna wire to slide freely as the kite moved around, while still being constrained in a sloper configuration parallel and adjacent to the kite line.

This is what I mean by that:

The entire kite set up looks like this:

Getting the kite to fly is simply a matter of holding it up into the wind, making sure there is tension in the kite line, and letting go so the wind will lift it. Once the kite is high enough to be in a steady stream of nonturbulent wind, very little needs to be done to keep it up.

And the entire operation looks like this:

Curious how well we did? You can watch a lot of the activation here!

Or just take a look at this map of our qsos (from qsomap.org). Yes, you ARE seeing that right. We got Alaska on our kite antenna! In all, we made 29 contacts.

What a thrill to fly an antenna on a kite! It has been on my mind to do this for months now and I am delighted by the accomplishment. I plan on experimenting more, including with a random wire, as well as configuring a ground wire to bleed off static. To be honest, now that I have the mechanism of securing a wire to a kite line figured out, using a kite as an antenna mast is actually a very easy (and tremendously fun!) thing to do.

So, with the very best of intentions, all I can say is:

GO FLY A KITE!

Yours truly,
KM1NDY