25 Years a Ham and Still Learning

I actually got my “ticket” a little late in life. I spent many years as an SWL, then college, career and a family took priority. By the time my wife and I became empty-nesters I had combined my passion for radio and Space “the final frontier” by chasing satellites; military satellites mainly. I formed the HearSat group dedicated to monitoring Low Earth Orbiting satellites. My account of a unique method of decoding the signals from Russian navigation satellites was kindly published by Monitoring Times magazine. At the time I felt there were so many fascinating signals flying around that there was nothing of value I could contribute by adding my own. However that feeling didn’t last long and eventually I bought a study guide, passed the written test and became a ham.

Now, I am into my 25th year in this great hobby. Frankly I was never satisfied with using a radio just to rag chew; I felt an urge to experiment – to contribute something useful to the science of radio communications. I didn’t fully realize it at the time, but I was at the bottom of a steep hill that I am still climbing, learning with every step. As my personal lifelong learning journey progresses I am proud to share knowledge gained here at Ham Radio Outside the Box.

“In times of change, learners inherit the earth; while the learned find themselves beautifully equipped to deal with a world that no longer exists.” – Eric Hoffer

Several weeks ago Ham Radio Outside the Box introduced a rather unique antenna idea, called the Coil-Loaded End-Fed Half Wave (CLEFHW). It is a telescopic whip that is inductively base-loaded to become an electrical half-wave. What is the purpose? To create a backpackable antenna with a very small footprint achieved by eliminating the need for a long counterpoise or system of radials. It worked very well – for a while. Then I began tinkering with it; I call it “continuous improvement” and it stopped working properly.

“If it ain’t broke …”

The antenna started to experience unstable SWR. Then the great snowstorms of February 2025 arrived and I could no longer get outside to investigate. Undaunted, I set up a wire in my basement “lab” to simulate the whip and was able to adjust the antenna to get a good SWR again. All was good – until an unusual warm spell hit and I was able to get out to a local park to do a POTA activation. Suddenly, the good SWR was gone again. Abandon the activation? No, improvise and adapt! I pulled my ham-brew “Old Barebones” Z-match out of my pack and finished the activation.

Back at the shack I was determined to find out what had gone wrong. The park I had visited sits on shale stone rock just beneath the soil and is right alongside one of the Great Lakes. Previous activations at that park had given spectacularly good results.

It ain’t gonna work John, give up and go have a beer

The snow still lay deep and crisp and even on my backyard but I managed to shovel my raised wooden deck clear and continue the investigation. That was the start of a very frustrating series of antenna trials. It can be tempting at times to quit – “it ain’t gonna work John, give up and go have a beer”. But, I remembered my college physics training: experiment – document the results – change one thing at a time – document the new results – make further changes as required and repeat until success is achieved.

The most important part of that process is to document the results at each and every step. I keep a small spiral bound notebook and a pencil nearby while I tinker in my basement lab. That makes it easier to review what went wrong and when. Yes, it’s tedious to put down the soldering iron and pick up the pencil, but it does make a big difference in the end.

So what was learned? It seemed a fair assumption that an 18.5ft whip, replaced with an 18.5ft wire would perform pretty much the same. But oh, no John, no John, no! There was another parameter involved that hadn’t been considered. The lab experiment with the wire took place in the nice, warm environment of my basement replete with space heater and a constant supply of hot beverages. But the basement lies 6 feet below grade – could that be an issue?

The carefully adjusted antenna with the 1.2:1 SWR was then carried up, up and away to the deck, out into the cruel Big Blue Sky Shack where the temperature was hovering around freezing. The 18.5ft wire was replaced with the telescopic stainless steel whip which, with all 13 sections extended, was also 18.5ft long. I confidently powered up my rig and set the mighty micro QMX to monitor SWR. “Should be pretty close to the same SWR I got in the basement” methought. But then disappointment haunted all my dreams. The lilliputian radio gave me the bad news: SWR 2.6:1.

A bit of a stretch

Previous learning experiences had taught that any physically short antenna that is artificially extended to it’s electrical full length by means of a loading coil tends to exhibit a very high Q. The CLEFHW uses a base loading coil to extend its physical length of 18.5 feet to an electrical length of approximately 33 feet which is a half wavelength on 20m. If the inductance of the loading coil isn’t right in the bullseye of the required value, the electrical characteristics can be subject to unexpected change.

But perhaps the unexpectedly high SWR out on the deck was influenced by another factor. Yes, the basement lab is 6 feet down below ground while the deck is 2 feet above the ground. How to compensate for this? Is the CLEFHW going to need a custom coil for each and every deployment? Maybe it will, but there is a solution that we will get to in a moment.

“If you want to find the secrets of the universe, think in terms of energy, frequency and vibration.”
― Nikola Tesla

Back in the lab the loading coil was rewound with nearly enough inductance to earn a place in Nikola Tesla’s lab.

The idea was that turns could be removed until the SWR settled down to an acceptable level. The target was less than 1.5:1. It worked! The SWR out on the deck came down to 1.10:1.

Just a cotton pickin’ minute Einstein…

The victory dance had to be put on hold as another doubt surfaced. The SWR measured out on the shale stone ground in the park was different to the SWR measured on the hardwood over concrete floor of the basement lab. The SWR out on the deck had been different again. A pause and a little stroking of the chin while the old gray matter overheated with intense thought. This deck, said the voices inside my head, is 2 feet above the ground. Do we have another variable to throw into the equation here?

The base of the antenna is at the top of the backpack frame and when the pack sits on the ground, as intended during outdoor operating sessions, it is only about a foot and half above the ground. The antenna is an almost vertical shortened End-Fed Half-Wave (it is sloped to give it some directionality). So is proximity to ground another factor to consider?

The whole backpack rig, antenna and all, was beamed over to an area of grass just beyond the deck. Here we go again, with everything exactly as it was up on the deck, the SWR grew legs and climbed up over 2:1 again.

The Ultimate Lossless Tuner?

The simple solution would have been to pull out “Old Barebones” (Z-match) again and bring those pesky standing waves under control. But I had another cunning plan. By leaving some extra turns on the coil I could increase the inductance beyond what is required to load the whip and use the whip itself to adjust the SWR.

Brilliant! It worked. The final iteration of the coil (nothing is ever really final) involves three taps near the top of the coil to leave some inductive flexibility to accommodate persnickety ground conditions. An SWR of 1.09:1 was obtained with the pack out on the grass. But, it was necessary to collapse two sections of the whip to get there. Interestingly, adjusting the whip length retunes the antenna without introducing any further loss; it simply restores the electrical length of the loaded whip to a half-wave.

So now, once again, the Ham Radio Outside the Box Coil-Loaded End-Fed Half-Wave antenna is ready for action. Lessons learned. Oh, and – Note to Self – move onto another project John – don’t tinker with things that work already!

Help support HamRadioOutsidetheBox

No “tip-jar”, “buy me a coffee”, Patreon, or Amazon links here. I enjoy my hobby and I enjoy writing about it. If you would like to support this blog please follow/subscribe using the link at the bottom of my home page, or like, comment (links at the bottom of each post), repost or share links to my posts on social media. If you would like to email me directly you will find my email address on my QRZ.com page. Thank you!

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How Can A Lossy Wire on the Ground Work Better Than A Quarter Wave Vertical Antenna?

Let’s get real here! If we lay a wire antenna on the ground, surely It can’t radiate more power than that cool-looking, expensive quarter-wave whip you just spent a small fortune to buy? Well, yes it can – but with a few caveats.

We can use a trick of geometry to support our claim. Our magic wire antenna has a footprint on the ground of only one square foot. The cool, costly ground-mounted whip has a footprint on the ground of only one square inch (ignoring the radial field). Bigger is better yes? Not convinced?

Okay, let’s unravel the geometric trickery while still maintaining our original claim. You might picture one square foot as a small square with equal sides of one foot. Therein lies the trickery. If we take 144 feet of wire of 1/12 inch diameter and tightly wind it into a square with sides of one foot, we’ll have a footprint on the ground of one square foot. Now let’s unwind that wire and stretch it out in a straight line along the ground. It is now 144ft long and 1/12 inch wide which is still one square foot.

Enough of the mathemagical sleight of hand; there is a much more convincing way of proving our point. Everybody knows that an antenna wire laid directly on the ground is lossy and, for once, everybody is right. But, only a few of us know how to take advantage of such a wire and make it a very useful antenna. I have personally enjoyed multiple QSOs with wires on the ground – despite the losses. I too was a skeptic until I actually tried it.

The theory of why it works has been covered in previous posts on this blog. The secret is that the wire has to be at least one wavelength (and preferably multiple wavelengths) long. The radiation pattern is a directional beam with low elevation.

As we can see in the far field plots above, EZNEC predicts an elevation angle of 25 degrees and a beamwidth of 54 degrees. However, the antenna has a loss of 3.9dBi. If we allow for the fact that some signal is also radiated outside the main beam, let’s treat that loss as, say, 5dBi.

Now compare that to our quarter-wave vertical for which we can estimate unity gain with a beamwidth of 360 degrees.

Now a clearer picture is beginning to emerge. If we calculate the RF energy within a beamwidth of 54 degrees for both antennas we can see how they compare. Let’s say our transceiver puts out 100 watts (I can hear QRP diehards loading for bear here). The lossy wire on the ground will only radiate 30 watts. The quarter-wave vertical will radiate all 100 watts but spread over 360 degrees. Within the beamwidth of 54 degrees, the vertical will radiate only 15 watts!

Gadzooks! A reel of wire costs only a few bucks but can radiate twice as much power as a shiny whip costing significantly more? Date check: yes it’s still January, not the first of April. Admittedly, this is a theoretical analysis lacking rigorous procedures for a proper engineering investigation. But, once again, I have personally made QSOs with more than one wire-on-the-ground antenna. Were my signal reports very poor? Absolutely not. This is not a spoof post, trust me.

There is another advantage of this wire-on-the-ground antenna when compared to a quarter-wave whip. Vertical antennas are generally considered to be susceptible to vertically-polarized noise. A wire on the ground is relatively immune to noise because of its inherent signal loss.

I don’t recommend selling your shiny, expensive whip and replacing it with some wire strewn across your backyard. However, imagine the possibilities when operating out in the Big Blue Sky Shack. A long wire can be concealed in a ditch, or in tall grass. Store it on a fly-fishing reel, then when you have finished operating simply reel it back in. It is the ultimate stealth antenna which could also be useful in a HOA situation.

Help support HamRadioOutsidetheBox

No “tip-jar”, “buy me a coffee”, Patreon, or Amazon links here. I enjoy my hobby and I enjoy writing about it. If you would like to support this blog please follow/subscribe using the link at the bottom of my home page, or like, comment (links at the bottom of each post), repost or share links to my posts on social media. If you would like to email me directly you will find my email address on my QRZ.com page. Thank you!

The following copyright notice applies to all content on this blog.

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.