Recent content by The DB

Sounds pretty complicated, if I get some more time this week I might try and get it into the modeling software... No guarantees though, I can't say translating that into a model will be easy... The DB

The ocf and fan dipoles are really two different antennas, and there really isn't much that is directly comparable. A few things I noticed while modeling these antennas. 1) With the fan dipole, it is easier to predict the radiation pattern. On some frequencies, the pattern of the ocf is...

I never could get the DDRR to model well, even if I used the double variant of it and mounted it in any number of locations. The Super Sinner would be great if most of what he wants to do is DX. It is horizontally polarized. There is a bug in both Nec2 and Mininec programs that appears to...

I've been playing with ground mounted antenna models just to see what I can find out. This is something I couldn't do with the nec2 engine as even with the best real ground, you could only get so close before it became inaccurate. As I now have a license for the nec5 engine, I don't have that...

Its actually not the connection to the earth itself that is causing that, its just that the connection to the earth changes things in such a way that that happens to have that effect. The same thing can be done without any earth present. Here is a hint that you likely don't need, what change...

So here I will start with a base model that shows a half wavelength antenna in a worst case scenario. In this case, the circle is the feed point. Everything above it represents the antenna, and everything below it represents the feed line. The green curved line is the current distribution...

That would have been me, I don't think anyone else used that name anywhere, at least radio related. It would have been years ago. All of the other forums I did anything I left for mostly lack of use. I have said many times that the optimal place for a choke on a 1/2 wavelength antenna is 1/4...

The only time an electrical half wavelength multiple lengths of coax have to come into play is using older models of antenna analyzers. Many newer designs have the ability to calibrate out such things, so in that case length doesn't matter so much. Also, such coax lengths are only good for one...

As I recall, that antenna mount has a permanently mounted coax cable. In that case, X and R will be off to some degree, but SWR will still be accurate. It is an effect of coax between the meter and the antenna. I wouldn't fret with those results at all. There are people who obsess over...

Crawdad is right, height really is might in this regard, the higher the antenna the lower the angle of radiation. To a lesser extent, the quality of of the earth below also plays a part. Seriously though, I wouldn't worry about the "take off angle" at all. Put up the antenna and see if you...

I used the file from Dan Maguire, it wasn't in those instructions, and its been long enough that I didn't remember. I unchecked it, and it worked, but every time I go back in after saving it unchecked, it is checked again... The DB

I had trouble getting NEC5 working with 4nec2. I had various settings set in 4nec2 that got in the way, I had to clear out and put a default install in, and after that NEC5 worked. Here is the g-max from above run with the NEC5 engine. I don't have to worry about AGT anymore because NEC5...

I actually started the process to purchase this software right after my last post... This is still nuts. At this point all I have are complaints. At the moment I have to wait one or two business days for an email to create an account to get access to software that I have already paid for...

You can use NEC5 with 4nec2? When the author gave his final update he specifically said he was not going to include NEC5 support, and I haven't looked into it since then, so this is news to me. As I look around the web for this, some people are saying that it appears to work, but the data is...

I have not used NEC5. I can easily afford it (even with its new three year license bs), but I can't really justify it, especially with how rarely I model anymore. Before this model I can't even tell you when the last model I made was? Was it within three years? If I do something I need it...