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It was what, six years ago I did the initial modeling on this? Marconi made some models as well. Unfortunately my models were lost due to a hard drive crash, well two drive crashes that were a few minutes apart from each other the second one killing my backup, but the threads are still here...

Wow, what a terrible attempt at trolling. I see the post you are responding to four pages ago, and of course, like a typical troll, you didn't even bother to link to it. Go figure. Physically, yes, no argument there, but physical length is not necessarily the same as electrical length. To...

@Dr_DX, you went beyond your own words in an effort to make your point. I always give props to people who post more than just their thoughts. Two things. One, something no one on this forum will argue with you on, yes, an electrical half wavelength of feed line will repeat the impedance of...

So, mind linking us to where some of this "well known ham's" said this? Or was this just a crutch to try and silence the person questioning your statement. The DB

This will be something that likely only the manufacturer will be able to answer, if they choose to. I don't know of very many people that will drop that kind of money just to find out the answer to that type of question on their own, and even if the world smiled on someone and these antennas...

The g7-144 covers the 2 meter ham band, so I'm guessing somewhere in the range of 144 to 148 MHz give or take. The g7-150-1 is advertised as covering 148 to 155 MHz, the g7-150-2 is advertised as covering 154 to 161 MHz, and the g7-150-3 is advertised as covering 161 to 168 MHz. The DB

Be careful with these tables. What they call "loss" isn't actually loss. The correct term would be "reflected", as that much power will be reflected, and I get how some would think that since it was reflected it was "lost", but in reality not all of it is, and in most cases, most of it...

This antenna has been modeled, although it has been a while for me. The radials don't really affect performance (gain) or the radiation angle of the antenna, and that holds for weather you have none, or 4 1/4 wavelength, or a bunch of shorter ones like this antenna, so as far as that is...

Its an acronym for "terminated end fed inverted vee antenna". The DB

Citation Needed, and with all due respect, its going to have to be one hell of a citation. I have run multiple tests with both types of coax and many others. LMR-400 works fine for radio. There is a very good reason that many think it is the best coax out there. Actually, if you bother to...

The models I made, and I think Marconi made as well we based on the exact dimensions of the antenna. You shouldn't have to do much of anything unless you have a problem. The DB

The angle of radiation for the 10 foot high antenna is 45 degrees, the 20 foot high antenna is about 25 degrees, and the 30 foot high antenna is 17 degrees. All this being said, I think to many people focus to much on this stat. There are far better things to focus on. This angle, in and of...

I have some models. Before I get into them, you should read the full post before just taking them for what you see. They are far enough outside of my expectations that I am questioning the results myself... The first of each pair of models is from the point of view of the side, and the second...

Actually, I do have another queation, what is this antenna made out of? Copper? Aluminum? Something else? The DB

Some people round the half wavelength length to 18 feet because it is easier, others use that length because they don't know any better. Also, to expand on what you noticed, if you take an antenna and move it around the chassis of a vehicle and measure it, you will notice that the tuned length...

No further questions, and sorry for the delay, life happens and as such I haven't had the time to sit down and make a model. I will make this model for you when I get a chance. The DB

I don't think the time domain is the cause. If it were, it doesn't explain why the X and Y axis does this, while the Z axis, alone, does not. I would still expect a dipole on any of the axis in free space to create the same pattern in relation to the dipole, and expect that pattern to have the...

The shield is attached to something that appears to be a boom, is that boom directly attached to the antenna's elements? Also, I can't read the writing on it, so how far past the front element does that boom go? The DB

Here is an attempt to show what I am seeing. I had to get out an older windows based laptop to use this tool as it doesn't work through wine on my current linux machine... Anyway, here is total gain, we are looking down the Z axis, the dipole antenna is on the X axis, which goes from left to...

I'm not so sure this antenna is radiating vertically polarized radiation anymore. In both nec2 and mininec, if I have a straight vertical center fed dipole (or in this case a straight wire on the Z or vertical axis), in free-space, all of its radiation is showing up as vertically polarized, as...