Difference in AstroPlane vs. New Top One per Eznec5

[bob85]

at that height they all look pretty miserable eddie, the dominant lobe up at high angles, i have seen models for 5/8waves show the same thing unless they are up at 2 wavelengths or higher to radials,
you missed the 4ft or less to test the uptilt claim, that would be a real cloudwarmer if its worse than your models on longer masts.

 

[HomerBB]

It looks awful, but it can talk pretty good with a blindfold on.

Did I see correctly that you had it at 46' high in one of them?
There was a discussion on a forum about the formulation of vertical lobes in a Quad beam that happened only within certain elevations. . .

 

[Marconi]

at that height they all look pretty miserable eddie, the dominant lobe up at high angles, i have seen models for 5/8waves show the same thing unless they are up at 2 wavelengths or higher to radials,
you missed the 4ft or less to test the uptilt claim, that would be a real cloudwarmer if its worse than your models on longer masts.

Here is a 3' mast model, and I guess we could say the pattern did uptilt. I don't think it was due to anything I did however, I think Mother Nature will probably do that to most antennas that low. I think the A/P has a problem with anything close to the big hoop at the bottom due to the heavy voltages that are likely flowing down there. I don't even see how any current from the part of the mast inside and around the area of the hoop can even pass that area with all the high impedance around, unless the voltage does get too far from the hoop, I'm sure that voltage doesn't radiate.

Such a pattern may be good for some DX since the wave front is broad in the desirable range of angles...pretty close to the horizon.

This is just a guess, but I think DX signals sometimes come in at all kinds of very low to medium low angles. In some cases such a pattern might even be better than a high gain antenna with a narrow lobe at 6* with a big null right above in the 12* - 25* degree range on some DX signals. There has to be some reason that the A/P is noted to work DX well, albeit may be the medium range stuff.

I like higher better though.

View attachment Bob's request for 3' feet.pdf

 

[Marconi]

It looks awful, but it can talk pretty good with a blindfold on.

Did I see correctly that you had it at 46' high in one of them?
There was a discussion on a forum about the formulation of vertical lobes in a Quad beam that happened only within certain elevations. . .

Homer, my original model that I was working with in this project was at 48' feet, and I've had models at different heights since.

I tried to always set the Antenna View to show the height in feet for the physical height of the A/P models. At any height the physical bottom of the antenna is always about 7.355' below the height of the mast with this model.

 

[HomerBB]

10-4

 

[nosepc]

AstroPlane Antenna V-101 is designed for 20 feet support mast, not more.

Their capacitances top hat should not be modified. different height gives different results.

For that reason, is no longer manufactured more.

Sirio TOP-ONE is an 1/4 ground plane antenna with top hat.

This is very different to ASTROPLANE AV-101..

"The Astroplane (AV-101) antenna.

Background.

The Astroplane antenna is a product of 1960s America. Citizen's Band radio was a 23 channel, AM only system and required a license to operate.
FCC restrictions limited the antenna height to 20 feet above the property, and most CB antennas would have been basic 1/2 or 5/8 wave monopole and base loaded types.
The Astroplane was designed to offer an improved radiation pattern, giving greater distance, while still allowing the antenna to be mounted on the roof without exceeding the height limit.

Astroplane

Design.

The antenna is designed to radiate maximum signal from the top section, sending the signal over roof tops to avoid the loss of signal through buildings.
Although the design is intended to have a 1/4 wave top section, this would make the antenna a total of 16 feet. As the antenna should have at least 8 feet of mast below it, the total when mounted would be more than the 20 feet maximum.
The answer was to use a shorter top section of around 1/8 wave length, and top load it to the 1/4 wavelength with a capacity hat (the top radials). This combination lowers the radiation angle, but also decreases the bandwidth.
For wider bandwidth use, this top section can be changed for a straight 1/4 wavelength section.

Quick Reference.
Creators:

Manufacturer:
Louis J. Martino,
Herbert R Blaese.
Avanti Communications

Specifications.
Claimed gain:
Impedance:
SWR:
Bandwidth:
4dBi.
50 Ohms.
Pretuned, below 1.4:1
27 - 29.7MHz.

Measurements.
Please note that component measurements are complete lengths. Once parts are slotted together, the electrical length may be different.
Full length:
Top section length:
Top Radials:
Bottom half length:
Loop Diameter:
Fibreglass rod length:
Mounting pole length:
12 Feet.
4 Feet.
4 of @ 24 Inches
8 Feet.
30.5 Inches.
13 Inches.
> 12 Feet."

 

[Marconi]

Nospec, the Patent was not done until 1970', so I'm not sure when the first hype came out about the Astroplane...including a lot of CBBS on the purpose for the idea and story why the AP only works low, or was designed to work low...like you suggest. Back then there was some FCC ideas about height in CB work, but I don't know anybody in the Houston, or SouthEast Texas area and the Gulf Coast that ever followed those rules...nobody. In the Valley with nothing but flat land from here to there, even 20' feet was not a big issue back in the 70's, but my Daddy always had a 100'-200' foot tower on his cotton farm and he had crews that worked his Field Services operations for several 100 miles up the I-35 and I-10 corridor

I find the antenna does work pretty well with a tip height no more than 20' feet high and for sure works better than a 5/8 wave with the tip at 20' and no more...with the 5/8 wave ground plane area buried about 3'-4' feet in the ground in order to try and keep the tip at or under 20' feet. Back in that time however most CB antennas that used a 1/4 wave radiator design or a 1/2 wave design were a little bit better off, in that regard, trying to work close to the Earth and stay within the 20' foot rule.

I guess Avanti's point was with a very short resonant 1/4 radiator on the top with a top hat to complete the 1/4 wave circuit...there was some advantage to be had with their design over the other designs.

Much like Coca Cola use to have cocaine as an minor ingredient, things change over time. It is alright now to come in out of the shadows of the old days, and put the AstroPlane up as high as you can get it, and see its performance shine, just like it did back in those days...if when guys followed the rules the A/P whipped all comers. The problem back then was I didn't know anybody that had a Starduster, Big Stick, or a HyGain CLR2, that didn't put those bigun's right up there on the top of the same pole they mounted their A/P on and there the old A/P took some what if a beating in the minds of CBr's anyway.

Do you, or have you any of these antennas, the old A/P, Top One, or the New Top One, and have you ever worked one? If not, I recommend any model will work just as good as any CB vertical out there...if you get the bottom of the antenna up as high to the mount. You might even see better signal reports at times from that little short radiator with a hat on top.

Thanks for the report. Have you got any pictures of you station?

Here are some images of my Top One with a full 1/4 wave radiator vs. New Top One. I also added a new project checking out a top hat radiator on my homemade Marconi 5x antenna just today. That Gain Master in the background is about 50' feet away, but my GM sees this antenna big time...I can see it on my meter. My Starduster is not show, but it is mounted about 6 feet lower and to the north, but it doesn't seem to effect the GM as best I can tell. My new GR 45 top radiator is fully top loaded, and that may make the difference even though it is only about 26' high while the bottom of the GM is 38.5' high.

BTW, in my real world testing here for the two A/P's I could see no difference in performance and the New Top One was mounted at the same height as the Old Top One...with the full 1/4 wave radiator. That said, the OTO was still higher by about 4'-5' feet. So, however we describe the New Top One...IMO it is every bit as good as the original A/P. Check my videos out in my signature below where I test some of my CB vertical antennas in a simple non-technical way.

 

[Marconi]

Update:

I have my Marconi 5x up, with the GR45 from Signal Engineering at about 21' feet. Earlier I had a 102" whip in the top for over a month. During that time I compared it with my SD'r at 46.6' to the hub, and my Gain Master at 38.5' feet to the base, both mounted at the same height to the bottom of the antennas...where both were at 55' and 61' feet to the tips.

Today I was working some DX with these on my switch box and I could hardly tell any difference at times. Some times however, the GR45 was about 3 sunits less, but the noise was less...so I could hear better. Of these three my original AS Starduster, at 55' feet to the tip, generally shows the best signal by a little bit, and is also very quite and also hears really well when conditions are not too noisy.

 

[CoAxed]

nice thread,
no mention of tagra`s Bt-101 ?
shame as it was excellent, anodised a gold colour too!

Query, I have a nice new sirio? astroplane/"top one" (plain brown box)awaiting installation. it appears the same as an av-101 (no gamma match) very confusing releasing 2 versions with the same name.

I never did get to try an atstrobeam..............I wonder...............

 

[nosepc]

This is my ASTROPLANE copy avanti AV-101, ALL manufactured in IRON.

I get better signal than a dipole, a loop and a slim-jim.

)

 

[Marconi]

This is my ASTROPLANE copy avanti AV-101, ALL manufactured in IRON.

I get better signal than a dipole, a loop and a slim-jim.

)

From my experience, if you get the bottom of the antenna above the top of the building a good 10' feet or more, you should be able to see a nice improvement in performance. Your building is likely blocking signals from that direction.

Your antenna looks just like an A/P.

 

[bob85]

have you tried modeling the astroplane upside down eddie?

 

[Marconi]

have you tried modeling the astroplane upside down eddie?

No Bob I have not turned an A/P model upside down, but I doubt it would make any difference...except maybe changing the maximum current height a little bit. I have done a Starduster upside down, but I'm not revealing what I see and think is going on there.

Why are you asking about the Astroplane and showing us and EzBob antenna view of a Sigma 4? Bob, it is good to be curious though.

I did two S4's tip to tip the other day at Donald's request for his idea of a collinear setup. I tried to follow up on that work about a week later, but that is when Donald refused to send me his collinear model. I wanted to see the real thing that tipped Donald off...as to how and why Eznec is junk. I could also stop guessing at what he wanted...so he could tell us what his point in asking me to model a collinear really was.

When I posted to him later asking if we could follow up, he said the model failed, and he wondered, what on Earth I wanted with a failed model and made a big deal out of that issue. I think he was frustrated, and he was just trying to be difficult at that moment. I just took him at his word, that he wanted to make a point when he asked me to make a collinear. I made 2 or 3 models trying to find one that he had in mind, but I think nothing made him happy at the time, and my crystal ball was broken. Obviously we never did get back to the point why he asked me to do such a model. We were just not communicating well at that time.

I think I have my Exnec model of the S4 fixed better in a couple of areas and it is showing better results, but I still don't see the gain in free space that Donald tells me that is what Sirio is reporting, free space gain.

Just today I emailed Sirio asking questions regarding the gain they reported for their NV4K, so hopefully they will set the matter straight whether the 4.15dbi gain they reported is over real Earth or in free space.

Today I also stepped back from my model and asked what is there that is not on my real S4. I fixed the end to end problems I found in the bottom hub and the radials, I also fix the end to end problems I found where the radials attach to the hoop. I had to redesign the hoop. I also took the compromise tubing diameter out of the bottom of my model and used one tapered connection on the radiator. These are issues that I've also been trying to suggest to Donald, that I think will help him with some modeling issues using Eznec, but I don't think he is interested.

That said however, I still cannot explain the difference I see in gain...if Donald is right and Sirio's gain is reported in free space. But if Donald is wrong I will make sure everyone knows.

I may be mistaken on some things, and I don't understand everything about antennas like some, but I'm not stupid enough to believe everything I hear either just because it is said by guys I like.

Right now, after my fixes I see a change in the currents on my S4 model, that I don't think supports my idea of cancellation anymore. I was surprised at one little thing making such a big difference. But for now that is my secret.

I believe I now see what Donald has tried to tell me from his real world testing...but if what I see is correct, and my currents still agrees with Donald's idea, then it is not Eznec that was wrong in Donald's bad experience, it was the modelers he used.

 

[bob85]

if you look at sirio's none cb antennas eddie you get more info, they are free space specs if you take 2.15dbi as a dipole or stardusters free space gain,
they claim the same gain for the vector as their other sleeve monopoles,

modeling the astro upside down is an idea for an alternative method of feeding a sigma style antenna.

 

[Shockwave]

No Bob I have not turned an A/P model upside down, but I doubt it would make any difference...except maybe changing the maximum current height a little bit. I have done a Starduster upside down, but I'm not revealing what I see and think is going on there.

Now we see who withholds information as opposed to sharing it when we find something good or useful.

Why are you asking about the Astroplane and showing us and EzBob antenna view of a Sigma 4? Bob, it is good to be curious though.

I did two S4's tip to tip the other day at Donald's request for his idea of a collinear setup. I tried to follow up on that work about a week later, but that is when Donald refused to send me his collinear model.

What I actually said was that the original shorted stub collinear model was modified into one with a helical coil and the one I wanted you to make with 4 wires added had not been saved. I specifically explained all you needed to do was add 4 wires but you proceeded to add an entire antenna.

I wanted to see the real thing that tipped Donald off...as to how and why Eznec is junk. I could also stop guessing at what he wanted...so he could tell us what his point in asking me to model a collinear really was.

That's why I posted a picture of exactly what needed to be added to your model. When you missed it once, I redirected your attention to the picture in another thread too. Once again it's post number 22 on the following page: http://www.worldwidedx.com/cb-antennas/159435-ghz24-what-your-opinion-sigma-4-a-3.html

When I posted to him later asking if we could follow up, he said the model failed, and he wondered, what on Earth I wanted with a failed model and made a big deal out of that issue. I think he was frustrated, and he was just trying to be difficult at that moment.

Sorry to say I think it's you that wants to be difficult. I even offered to add the 4 wires to your model if you wanted to send it to me. It's seems your goal is to debate rather than to learn or assist others in the same.

I just took him at his word, that he wanted to make a point when he asked me to make a collinear. I made 2 or 3 models trying to find one that he had in mind, but I think nothing made him happy at the time, and my crystal ball was broken.

It does not feel like you've taken my word for anything Marconi. If you did you would stop relying on your crystal ball and just read and look at the pictures I've posted outlining the 4 wires. That would make me happy.

Obviously we never did get back to the point why he asked me to do such a model. We were just not communicating well at that time.

I think I have my Exnec model of the S4 fixed better in a couple of areas and it is showing better results, but I still don't see the gain in free space that Donald tells me that is what Sirio is reporting, free space gain.

Just today I emailed Sirio asking questions regarding the gain they reported for their NV4K, so hopefully they will set the matter straight whether the 4.15dbi gain they reported is over real Earth or in free space.

That's what I mean when I say it doesn't feel like you take my word. 4.15 dbi is 2 dbd. They have already given you the free space gain and the gain you can expect over real ground when replacing a dipole. If you think these gain figures are not in free space I have to ask where is the gain from the added ground reflections? What height above ground would these tests have been done at? With every foot change in height, the gain above real ground will change accordingly. This is why ONLY free space gains are reliable in the first place.

Today I also stepped back from my model and asked what is there that is not on my real S4. I fixed the end to end problems I found in the bottom hub and the radials, I also fix the end to end problems I found where the radials attach to the hoop. I had to redesign the hoop. I also took the compromise tubing diameter out of the bottom of my model and used one tapered connection on the radiator. These are issues that I've also been trying to suggest to Donald, that I think will help him with some modeling issues using Eznec, but I don't think he is interested.

That said however, I still cannot explain the difference I see in gain...if Donald is right and Sirio's gain is reported in free space. But if Donald is wrong I will make sure everyone knows.

That's what it feels to me is important to you. Making sure everyone knows if Donald is wrong about how the Sigma design works. Let me save you the time. It's never going to happen in any significant way. It took me 15 years of working with the design every day to understand what I do about it today. You will never change field testing results obtained by many unbiased sources during that time frame.

I may be mistaken on some things, and I don't understand everything about antennas like some, but I'm not stupid enough to believe everything I hear either just because it is said by guys I like.

That sentence leaves me with some doubt. You'll ignore someone with experience in over 1000 installations of a specific antenna in favor of your one time experience and working with a software program that has not demonstrated any ability to accurately model the antenna. No offense but that sounds stupid to me.

Right now, after my fixes I see a change in the currents on my S4 model, that I don't think supports my idea of cancellation anymore. I was surprised at one little thing making such a big difference. But for now that is my secret.

Notice your ideas on how it works change regularly because they have no foundation to support them in the field? On the other hand, my findings have not wavered a bit in years because I know how it works beyond any doubt and it was no easy journey to get here. You've also made it clear again that you are the one with the desire to withhold information you feel is important. Way different than how I operate here. This takes place at the same time you accuse me of the very thing you're bragging about doing.

The good news is if you really did fix the model so EZNEC works, all you have to do is add those 4 wires to test it. If you still have to invert the phase 180 degrees to add another 1/2 wave on top, you can throw that model in the trash too.

I believe I now see what Donald has tried to tell me from his real world testing...but if what I see is correct, and my currents still agrees with Donald's idea, then it is not Eznec that was wrong in Donald's bad experience, it was the modelers he used.

Now you're getting close to the point I was trying to make but I still don't think you see that you're even warm yet. It's not "the modelers he used" it's every model anyone has ever shown me on the design in EZNEC that has failed. The point was to apply my test to any new model to see if anyone could get EZNEC to show any result remotely close to what we see in the field. That's why you need to add the 4 wires to your model and stop trying to nit pick on the ones I have that already failed.