Outdoor Loop

[BOOTY MONSTER]

i'm still impressed it was going back and forth with the v4k with each winning at times . it was also at a lower feed-point height and about 35 ft lower than the v4k's tip height . its also much much cheaper and easier to make . i definately want to try one in the next few months .

homer is a real inspiration and his contributions makes this a better forum .
you da man HBB

 

[HomerBB]

Hopefully in the next few days I'll be mounting a 2 element Quad.

 

[wavrider]

Hopefully in the next few days I'll be mounting a 2 element Quad.

For the ease of construction, hard to beat a quad,

On the other hand a moxon is easier, lighter weight, and will perform just as well as two element quad.

 

[HomerBB]

Quad is prettier.
And if Doc has anything to say about it, prettier yet in pink.

I have serious doubts the Moxon will perform as well as the 2 element Quad. :blink:
It is commonly held that a full-sized 2 element Yagi will outdo the Moxon in gain, and that the 2 element Quad will be better by a little than the 2 element Yagi nearly matching the performance of a 3 element Yagi. The only advantage of the Moxon over the 2 element Yagi is its very small footprint, and a superior F/B. At least this is my understanding, and it has influenced my decision to make a 2el Quad instead of the Moxon.

Making the Moxon would be simpler. Narrow the angle between the two sides of my square quad (15 minutes). Separate the loop on those two narrow sides at the appropriate point (10 minutes). Remove the 75 Ohm section from the feedline (1 minute). Remount the Moxon and key up (5 minutes). In about 1/2 hour I would be flying the Moxon.

But the quad is still prettier.

 

[wavrider]

The quad vs yagi discussion.

Google is a friend here so I will not need to go into a long explanation. Basically the test results found no performance advantage with a quad over a yagi.

The quad will perform as designed at the frequency it was designed for.
The further away it is operated off of the design frequency the less performance it will have. In other words it may have 6DB of gain at the design freq, say 27.5 for discussion. VSWR may permit it to operate at 27.0 but it will not have 6DB of gain at that freq.

The moxon will have uniform gain across the entire use able bandwidth.

The quad if built with wider element spacing will indeed outperform the moxon, but not a noticeable difference on the receive end.

 

[wavrider]

[But the quad is still prettier. [/QUOTE]

They do look impressive in the air

 

[Robb]

I don't know about it being pretty.

However, it is quieter. That is a usable feature all on its own IMO. A receive that is maybe a db or three quieter on a Quad compared to a Yagi can make a difference in a station that is already difficult to hear. If the gain is the same between a Yagi and a Quad but hearing less noise on the Quad; then it is still the better antenna. And yes; that was one of the conclusions from a previous thread on 'Quads vs Yagis'. The difference is also in cost - obviously the Quad is more expensive compared to a Yagi.

Having said that, I would easily pick the 2 element Quad over a 2 element Yagi or a Moxon.

 

[wavrider]

I don't know about it being pretty.

However, it is quieter. That is a usable feature all on its own IMO. A receive that is maybe a db or three quieter on a Quad compared to a Yagi can make a difference in a station that is already difficult to hear. If the gain is the same between a Yagi and a Quad but hearing less noise on the Quad; then it is still the better antenna. And yes; that was one of the conclusions from a previous thread on 'Quads vs Yagis'. The difference is also in cost - obviously the Quad is more expensive compared to a Yagi.

Having said that, I would easily pick the 2 element Quad over a 2 element Yagi or a Moxon.

I agree the quads are quieter on receive, I have ran a few on different bands and they are quieter, especially in a windy location or a wet location, lots of rainfall.

So ROBB how many moxons have you built and compared the quad to?

 

[Needle Bender]

The quad vs yagi discussion.

Google is a friend here so I will not need to go into a long explanation. Basically the test results found no performance advantage with a quad over a yagi.

The quad will perform as designed at the frequency it was designed for.
The further away it is operated off of the design frequency the less performance it will have. In other words it may have 6DB of gain at the design freq, say 27.5 for discussion. VSWR may permit it to operate at 27.0 but it will not have 6DB of gain at that freq.

The moxon will have uniform gain across the entire use able bandwidth.

The quad if built with wider element spacing will indeed outperform the moxon, but not a noticeable difference on the receive end.

many say a quad isnt better then a yagi and I can write a complex British term which concisely expresses my opinion of that - rubbish

 

[Robb]

I agree the quads are quieter on receive, I have ran a few on different bands and they are quieter, especially in a windy location or a wet location, lots of rainfall.

So ROBB how many moxons have you built and compared the quad to?

Simple answer - none. Never built a Moxon. Had a 2 element Quad before. If I was to build anything, I would build a 4 element F-Yagi. It s similar to a regular Yagi - except the drive element is a folded dipole/loop.

"dd18" WWRF member/91DD018's site:
5 Element LFA Yagi | 91DD018

Quiet. Wide bandwidth for same amount of elements used compared to a standard Yagi. 50 ohms impedance and no balun needed. Much better F/B rejection than a standard Yagi. Better side rejection and slightly better gain too. Did I say that it was quieter already?
Yup.

Henry HPSD's site:
f-yagi 11-3s

 

[HomerBB]

The quad vs yagi discussion.

Google is a friend here so I will not need to go into a long explanation. Basically the test results found no performance advantage with a quad over a yagi.

The quad will perform as designed at the frequency it was designed for.
The further away it is operated off of the design frequency the less performance it will have. In other words it may have 6DB of gain at the design freq, say 27.5 for discussion. VSWR may permit it to operate at 27.0 but it will not have 6DB of gain at that freq.

The moxon will have uniform gain across the entire use able bandwidth.

The quad if built with wider element spacing will indeed outperform the moxon, but not a noticeable difference on the receive end.

Wasn't wanting to introduce a debate, just express why I preferred to put up the Quad. I haven't compared a Moxon, but maybe I will in due time.

 

[wavrider]

Simple answer - none. Never built a Moxon. Had a 2 element Quad before. If I was to build anything, I would build a 4 element F-Yagi. It s similar to a regular Yagi - except the drive element is a folded dipole/loop.

"dd18" WWRF member/91DD018's site:
5 Element LFA Yagi | 91DD018

Quiet. Wide bandwidth for same amount of elements used compared to a standard Yagi. 50 ohms impedance and no balun needed. Much better F/B rejection than a standard Yagi. Better side rejection and slightly better gain too. Did I say that it was quieter already?
Yup.

Henry HPSD's site:
f-yagi 11-3s

ROBB I looked at that a while back, impressive, I do like the folded dipole for a driven element.

 

[wavrider]

Wasn't wanting to introduce a debate, just express why I preferred to put up the Quad. I haven't compared a Moxon, but maybe I will in due time.

I have always liked a quad, two element is easy to construct, easy to match using 75 ohm coax, and the band width is very nice also.

Friend of mine likes to use JT65 mode, it is great to compare receive signal strength on different type of antennas, rx signal strength is shown in the software displayed. The moxon surprised me on the results for F/B. For a couple of pieces of wire it is impressive.

 

[HomerBB]

Today I constructed a reflector and put it on the boom with the driver. Tomorrow I hope to finish it and see how it does. After that we'll see about perhaps making it dual polarity. . .

 

[wavrider]

How far apart do you plan to space the reflector from the driven element? It will influence the impedance of the antenna adding that reflector but hopefully not to much. If you can space it about 6' from the driven element it should work out pretty good that is .2 WL of spacing.