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ASTROPLANE best vertical antenna ever?

Marconi,

After all of your years of research, personal experience, and reports from other users, which version do you feel provides the best overall performance? Avanti Astroplane, Targa version or Sirio Tophat? By your video the Tophat certainly seems to win in the noise floor category.
 
Hello
I have a question that i noticed in the original patent for the Avanti Astroplane.
On Page 6 under section 10 which i highlighted in blue it talks about efficiency.
My question for those who understand the details about how antenna theory is
By removing the top hat does that make antenna work better as long as the SWR
stays in range. Also for my use i do not stray above or below 1-40?
I am curious as this is out of my area of knowledge.
The attach file is the PDF of the patent for the Astroplane and Astrobeam.
 

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Hello
I have a question that i noticed in the original patent for the Avanti Astroplane.
On Page 6 under section 10 which i highlighted in blue it talks about efficiency.
My question for those who understand the details about how antenna theory is
By removing the top hat does that make antenna work better as long as the SWR
stays in range. Also for my use i do not stray above or below 1-40?
I am curious as this is out of my area of knowledge.
The attach file is the PDF of the patent for the Astroplane and Astrobeam.

This is the specific text he has highlighted.

This is especially so when the conductor 46 is one-quarter wavelength, for the efficiency drops somewhat for a broader band when the conductor 46 is capacitively loaded, as by the crossed conductors 48 and 50.

When you add a capacity hat to a 1/4 wavelength antenna element, efficiency goes down. This is a form of loading and all forms of loading have this effect. But this is also that "less efficient" statement that so many people get hung up on, when nothing is said about how much less efficient. As is almost always the case when this phrase is invoked, in the real world it isn't so much that you will notice the difference so I wouldn't worry about it.

The Astrobeam came with a straight upper element, and there was a version of the Astroplane that also came with a straight upper element as well, although not as many of those were sold. I have also heard from others who have changed out the cap hat for a straight element as well, so it has been done.

I wouldn't worry about it if your just staying on the regular 40 channels. The CB band is a very narrow band, and very few antennas struggle to have enough bandwidth for it, and when they do there is typically a reason for it. The Astroplane design should have plenty of bandwidth with or without the cap hat.


The DB
 
This is the specific text he has highlighted.



When you add a capacity hat to a 1/4 wavelength antenna element, efficiency goes down. This is a form of loading and all forms of loading have this effect. But this is also that "less efficient" statement that so many people get hung up on, when nothing is said about how much less efficient. As is almost always the case when this phrase is invoked, in the real world it isn't so much that you will notice the difference so I wouldn't worry about it.

The Astrobeam came with a straight upper element, and there was a version of the Astroplane that also came with a straight upper element as well, although not as many of those were sold. I have also heard from others who have changed out the cap hat for a straight element as well, so it has been done.

I wouldn't worry about it if your just staying on the regular 40 channels. The CB band is a very narrow band, and very few antennas struggle to have enough bandwidth for it, and when they do there is typically a reason for it. The Astroplane design should have plenty of bandwidth with or without the cap hat.


The DB
Thank you very much for the explanation! I have run this original Avanti Astroplane for the last 8 years. I bought it new and for me it has worked amazingly. I was looking for the patent for the Astrobeam hoping to find enough
details so that i might try to build my own.
This is the specific text he has highlighted.



When you add a capacity hat to a 1/4 wavelength antenna element, efficiency goes down. This is a form of loading and all forms of loading have this effect. But this is also that "less efficient" statement that so many people get hung up on, when nothing is said about how much less efficient. As is almost always the case when this phrase is invoked, in the real world it isn't so much that you will notice the difference so I wouldn't worry about it.

The Astrobeam came with a straight upper element, and there was a version of the Astroplane that also came with a straight upper element as well, although not as many of those were sold. I have also heard from others who have changed out the cap hat for a straight element as well, so it has been done.

I wouldn't worry about it if your just staying on the regular 40 channels. The CB band is a very narrow band, and very few antennas struggle to have enough bandwidth for it, and when they do there is typically a reason for it. The Astroplane design should have plenty of bandwidth with or without the cap hat.
 
A traditional well elevated 1/4 wave is no slouch on 10m/11m. It will DX as well as
a 1/2 wave and correctly installed 5/8th wave.

1/4 waves on the ground for 10m and 11m is where they do you no favours at all.

They will work in strong conditions but they will be outperformed with ease by a 1/2 wave at 10 meters feed point.

It comes as no surprise that an Astroplane type antenna works similarly when well elevated.
 
So after all those posts, is it the best? I like mine but with all the good and not so good arguments made in this thread, I feel there was no consensus. Each his own.
 
Questions such as "is it the best?" seem pointless as any antenna may be fabulous in a certain situation and be a POS in a different one. If your antenna does what you want it to and you like it, then anyone else's opinion doesn't have much value. Concensus on RF topics are about as rare as hens teeth.

7 3
 
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Saw lots had the Astroplane back in the 60's and 70's but in my opinion it was just a glorified 1/4 wave! My 5/8 CLR II was much better! It always goes back to the old saying "The bigger the junk iron you got hanging in the air, the better it will work"
 
I talked to a guy in NY today who was transmitting on really old Shakespeare big stick and it was making the trip really well.

Like o'l @Crawdad said, old junk to some but in this case it's was working well.

Different folks Different strokes
 
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I talked to a guy in NY today who was transmitting on really old Shakespeare big stick and it was making the trip really well.

Like o'l @Crawdad said, old junk to some but in this case it's was working well.

Different folks Different strokes
I remember the Big Stick. Everyone had them back in the day. Seemed to be the Antron 99 of the 70s and 80s.
 
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I remember the Big Stick. Everyone had them back in the day. Seemed to be the Antron 99 of the 70s and 80s.
Radio Shack actually sold the original Shakespeare Big Stick back in the late 1970s and early 1980s. This was long before they had Archer make their junk blue copy of the antenna, with the "100 watt fuse" in the base. I've seen bigger toroids in a 300 to 75 ohm TV antenna transformer.
 
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