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Marconi · #89 12-09-2011, 09:19 PM

Quote:

Originally Posted by HomerBB

So, will E5 allow us to split and feed the two wires at two of the corners on the sides?

Homer, I'll try this one tomorrow, but I don't think it will be a true quad when finished, like 'Doc suggested.

Check this out.

http://www.signalengineering.com/Th8.jpg

Needle Bender · #90 12-10-2011, 01:43 AM

Quote:

Originally Posted by HomerBB

Well, that is more interesting. There is that big blob striaght up, though. I've seen this antenna configuration dicussed, but I fail to see why one would do it given most of the power goes straight up into that Elmer Fudd head shaped pattern.

Thanks for doing it.

no no no, you have to look at the green dot! you would have a 12 degree angle at the highest gain lobe of 5.56dbi or about 3.5dbd!

hey marconi, can you do that model looking straight down on it from space? i want to see the polar pattern.

HomerBB · #91 12-10-2011, 06:19 AM

Quote:

Originally Posted by Marconi

Homer, I'll try this one tomorrow, but I don't think it will be a true quad when finished, like 'Doc suggested.

Check this out.

http://www.signalengineering.com/Th8.jpg

Now you do see what I mean. That's fed at the sides, too.

HomerBB · #92 12-10-2011, 06:21 AM

Quote:

Originally Posted by W5LZ

Sorry about the 'NVIS'/'Nevis' thingy, even misspelled you get the idea.
I used an antenna called a NVIS to do phone patches during 'Desert Storm'. That 'short range' type of qualification/classification is very vague to say the least. Admittedly, the propagation was much 'better' than now, but still, that 'straight up' thingy isn't as sure a bet as you might think.
About that 'diamond' shaped quad thingy. Yes, it can work and be directional. There are several antennas of that sort. Would two quads be better than using two other types of antennas (or more than two)? I don't know, but I sort of doubt it. It would be the equivalent of two single element quad antennas pointed in different directions. Using dipoles instead of a loop means that the resulting antenna would be a two element directional antenna (Super Scanner??). Different shaped/styles of antennas have different characteristics in them selves. I like loops, but they get sort of bulky/cumbersome, you know?
- 'Doc

I'm wondering if it would have omni-directional properties, and if so would there be good gain, and decent bandwidth . . .

HomerBB · #93 12-10-2011, 06:23 AM

Quote:

Originally Posted by Needle Bender

no no no, you have to look at the green dot! you would have a 12 degree angle at the highest gain lobe of 5.56dbi or about 3.5dbd!

hey marconi, can you do that model looking straight down on it from space? i want to see the polar pattern.

yes, a top view would be nice

Marconi · #94 12-10-2011, 07:16 AM

Quote:

Originally Posted by Needle Bender

no no no, you have to look at the green dot! you would have a 12 degree angle at the highest gain lobe of 5.56dbi or about 3.5dbd!

hey marconi, can you do that model looking straight down on it from space? i want to see the polar pattern.

I agree with you NB. Here are the physical view and azimuth plot of Homer's quad idea with the feed points to the sides.

There is a Freecell discussion on this forum about this SE antenna, and I think he is suggesting the opposing wires are co-phase fed and both are radiating a bid-directional pattern like I think you are imagining.

Homer's quad idea from the top.pdf

HomerBB · #95 12-10-2011, 01:24 PM

From the looks of that radiation pattern, it looks nearly perfectly omni-directional.

Marconi · #96 12-10-2011, 04:31 PM

Quote:

Originally Posted by HomerBB

From the looks of that radiation pattern, it looks nearly perfectly omni-directional.

The co-phase #2 model does seem to produce a nice omni pattern in free space with the co-phase setup turned on, but it too has a very bad match that would have to be fixed. As it is now this one shows SWR over 20:1 and both resistance and reactance are way high.

I'll try to model the SE antenna tomorrow maybe. Like I said earlier, this one has the wires insulated at each end, unlike my original model of your idea for two quad elements bisecting each other.

So far all iterations I have made result in very high matching numbers, and to fix those may result in additional losses and reduced gain. I also note that these buggers don't allow me to attach a conductive mast to the bottom without the pattern and currents going to heck in a hand basket and I don't seem able to reproduce anything near the 0 degree maximum angle that SE shows on their old Website. Maybe FreeCell was right. The wires may be co-phased, or delay phased in such a fashion with two opposite wires...each radiating together when used to produce a bi-directional beam pattern. The RF may be radiating from each wire like a dipole and not bisecting the quad loop as we typically imagine.

BTW, unless the match is close, I'll not be able to show any bandwidth. The SWR generator will be off the chart at 20:1 SWR or more. Does your quad show a much better bandwidth than your sleeved dipole or your yagi beam?

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