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So, this is an antenna that is between 5.5 and 6 feet long and it uses a planar loading coil. All a planar coil is is a flat coil, nothing more. They also loaded part of it up with, essentially, techno mumbo jumbo as read from the antennas manufacturer's literature. MEG... It stands for Mean...

That is true. Just raise hell until they put them all underground in the areas you drive... ;) A friend of mine used to run an autotuner right before a 102 inch whip on his pickup truck (mounted front left corner of the bed). He loved it, then when he got a new vehicle, at the suggestion of...

Assuming the same mounting place, and a remote autotuner, you would get better performance if you used the 15 meter 1/4 wavelength length. In fact you can comfortable go longer than that by quite a bit. The DB

Common question. It shows up here every so often. If you don't have any problems with the antenna setup, then adding the radial kit will make so little a difference you will never notice it. There are, however, problems that said radial kit will fix, in which case you very well may notice a...

I remember those days. Said amps would be run on the ragged edge to the point where everything had to be perfect, and even with said perfection, many dind't last long even when run at 12 volts and under ideal circumstances. The problem is many people bought said amps thinking they were "the...

That is an option, and if you or the op chose that path I would have no complaints. In fact, it was listed at the top of my recommended list. Although calling it "maximizing efficiency" is at best a stretch, especially from someone who is willing to "deal with" said additional loss. The OP...

The problem is the fact that the antenna isn't going to be a tuned antenna. Lets take a look at what happens to said efficiency when SWR goes up, this is with 220 feet of LMR-400 at 27.2 MHz. Here we have SWR in the first column, dB loss in the second column, and percent of transmitted power...

There are several options. 1) You can measure the impedance of said antenna and build an antenna tuner for it. This would allow the use of said LMR-400. You would get 1.397dB of loss in the coax (or with 100 watts in you will get 74.495 watts out) and a little more in the matching circuit...

I would start with four 1/4 wavelength radials at the height of the vehicle's roof. Easy to make and typically very effective. Looking at the model, when it comes to a segment at the end of the wire and placing a source there, make sure the end of the wire is connected to other wires. If it...

I model primarily in 4nec2, but both EZnec and 4nec2 use the same nec2 engine. When modeling a coil, the software will make adjustments on inductance and capacitance within that coil, but most people use small straight lines, and because of that, what the software calculates will be off to some...

If changing the routing or location of the coax changes SWR then you have one of two issues. Essentially the easy description for both of these is you have antenna currents flowing at places you don't want them. The most common cause is common mode currents. A lot of people will falsely...

There is no noticeable difference between SWR and Resonance. There is also no noticeable difference between 2:1 SWR and 1:1 SWR. The difference in both of the above is so small you will never notice the difference. In most cases, getting that antenna 5 feet higher will make more of a...

There are three different ways to design a Yagi antenna with three or four elements. One is gain, a yagi antenna with peak gain in the forward direction tends to have a pretty significant secondary lobe facing the opposite direction. I actually know a ham that thought his antenna was pointed...

So you mentioned above 37 ohms and now you post a picture and reference to something that says 35 ohms. I guess they are somewhat close relatively speaking... I would have so many questions about the antennas you made and how you measured them that it isn't even funny. Based on my experience I...

I'm curious as to where you got this idea, its at least the second time I've seen you post this. The problem is, it isn't true. If a 1/4 wavelength vertical antenna is over a perfect ground, then it will have 36 or 37 ohms of impedance. But four radials does not a perfect ground make. The...

The speed of light is 11,802,852,672 inches per second The frequency for CB channel 20 is 27,200,000 Hz To get the wavelength take the speed of light and divide that by the wavelength... 11,802,852,672 ÷ 27,200,000 = 433.9284... Then divide that by 4 for 1/4 wavelength... 433.9284... ÷ 4 =...

I've said several times in this thread and elsewhere that you won't notice the difference between however you choose to tune your antenna, included in that quoted post. Part of the point of the thread was to challenge a concept that is widespread but no one has ever demonstrated before. The...

If you look under DX Gallery link above and click on my name, in there is an album called "Does resonance show max gain?" This has the images that were used in the initial post of this thread. Back when I posted it, I was able to link the images in an album on this forum directly into a post...

Looking at these models closely, I'm curious where you got these models? The first and third models, that is the Sirio SY 27-4 which is said to be from the Sirio web site, and the Maco M103C which is said to be from the Maco web site. The curious thing about these two models is they screem...

According to This coax loss calculator, a 150 foot run of RG8x with a 1:1 match on the antenna end, 100 watts in will get you 58.498 watts absorbed by the antenna. There is 2.32 dB of loss, all of it from the initial pass through the coax. According to the same calculator, a 150 foot run of 450...