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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.

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The year is leaving us 😿
here's a rough draft for 2025:

#AlternateFridayMusic

Jan 03 #Asylum
Jan 17 #Battery
Jan 31 #Colour
Feb 14 #Denial
Feb 28 #Elevate
Mar 14 #Forever
Mar 28 #Gather
Apr 11 #Horrible
Apr 25 #Insect
May 09 #Jerk
May 23 #Karate
Jun 06 #Lies
Jun 20 #Myth
Jul 04 #Never
Jul 18 #Opportunity
Aug 01 #Pop
Aug 15 #Quiet
Aug 29 #Robot
Sep 12 #Simple
Sep 26 #Technique
Oct 10 #Universe
Oct 24 #Vast
Nov 07 #Work
Nov 21 #Xer (generation)
Dec 05 #Yank
Dec 19 #Zombie

#FortnightFridayMusic

Jan 10 #Zoo
Jan 24 #Youth
Feb 07 #Xeno-
Feb 21 #West
Mar 07 #Void
Mar 21 #Utopia
Apr 04 #Terror
Apr 18 #Substance
May 02 #Release
May 16 #Quasi
May 30 #Prove
Jun 13 #Omen
Jun 27 #Nowhere
Jul 11 #Movement
Jul 25 #Lounge
Aug 08 #Kick
Aug 22 #Jam
Sep 05 #Imagination
Sep 19 #Home
Oct 03 #Ground
Oct 17 #Fountain
Oct 31 #Electric
Nov 14 #Defend
Nov 28 #Captive
Dec 12 #Breakups
Dec 26 #Apathy

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‘It is all lining up’: Plan for #Ukraine to finally start using #F16 jets this summer
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