Any Astro Plane Fans ?

[Marconi]

jazz,
if Henry ( top guy in my book ) had not helped out dealing with the guy i would not have an astroplane on its way to me

Bob, good luck with you new antenna, but be on notice that they can be very nasty if you try and put a lot of power in them. There designed to be a balanced center fed 1/2 wave, but their balance is way missing as a general rule. They work fine working CB or QRP, and experience tells me they are very effective in spite of all the TVI they can produce. Get every part nice and tight without over doing it. I replace all of the hardware with Stainless, and with all the wind you get...it might be a good idea to reinforce the bottom hoop to the mast. Generally speaking they are typically very sturdy in the wind except for the bottom of the hoop can move around a lot.

IMO, I like this center fed 1/2 wave, because it is very big without being heavy, and thus it has great ears when conditions are quiet. I also find 36' feet is not a good height for this antenna for some reason. I only use a 50' foot feed line or multiples on it too. I've found that length tends to settle the TVI down some. The A/P does like to be high if you can get it up there in your area.

Seriously Bob, good luck.I'm glad to see you finally get one of these. I think you will get the most out of this antenna and report back some good news.

If you decide to put a full 1/4 wave radiator on it...I found the length to be close to 87.5" inches with at least 43" x 1/2" section hose clamped to the side of the stock element.

Keep me posted.

 

[bob85]

i don't think i will have cmc issues if i isolate the antenna 1/4wave below the hoop eddie,
folk claimed the sigma4 was bad for cmc,
its no different than the i-10k for me, neither give any trouble up to 1kw and i don't run anywhere near that nowadays.

 

[222DBFL]

Marconi how high up is your top one antenna? Doesn't look very high up in the photos. And as far as size does it take up much space? May try one of these next if they don't have to be setup real high, say 20-30ft to base Max. Thanks for any and all info.

 

[Marconi]

Marconi how high up is your top one antenna? Doesn't look very high up in the photos. And as far as size does it take up much space? May try one of these next if they don't have to be setup real high, say 20-30ft to base Max. Thanks for any and all info.

222, the bottom of the ring of the New Top One is about 20' feet high, so the tip is at about 32' feet, and the feed point is at about 28'-29' feet. The GainMaster is about 60' feet to the tip and about 38' feet to the feed point or coax connector.

The widest point on the NTO antenna is at the hoop at 30" inches and the top hat at about 28" inches on each side.

 

[Marconi]

i don't think i will have cmc issues if i isolate the antenna 1/4wave below the hoop eddie,
folk claimed the sigma4 was bad for cmc,
its no different than the i-10k for me, neither give any trouble up to 1kw and i don't run anywhere near that nowadays.

Here is my Eznec model with a full 1/4 wave radiator as 32' feet, 36' feet, and 36' feet with the mast isolated about 97" inches below the bottom hoop.

Bob you look to be right...this does reduce the currents flowing on the mast and the mast inside and right below the antenna. I isolated the mast with 6" inches, and I used 97" inches below the hoop...just a wild guess.

In the past I did not compare antennas when DX was working. And, I don't recall ever using my A/P during skip periods in the past. I was a bit surprised that I did not observe any advantage due to a horizontal beam...while I was contesting this past weekend.

I do remember years ago comparing an A99 and my Old Top One with a buddy about 5 miles away on his A99 and his 5 element horizontal Maco, but back then I saw a much better signal response from his beam when I was switched to my A/P. The A99 receive signal dropped noticeable when WJ was on his beam, and we saw the opposite both directions when I got on my A/P.

I know that DX signals typically vary noticeably, but I thought I still might see some difference, that is why I choose my New Top One to put up. I should have used my Marconi, and I will do that if we have another contest...and the Good Lord is willing.

 

[222DBFL]

Thanks Marconi exactly what I needed sir!!

 

[tuner]

I hope you guys don't mind I think ill share this info on my Astro Plane FB group

 

[Marconi]

Tuner it is Ok by me.

 

[bob85]

changed my mind about avanti antennas? no eddie,
though i do think they were guilty of trying to pull the wool over our eyes with their claims about prior art antennas,

the sigma4 does provide more signal at low angles than any 5/8wave when mounted on the same pole, for me the adjusted vector does even better but the vector build quality is poor,

it looks likely it may not do it as i first imagined and for sure the increased height of current maxima is a vital part of the equation,

i still don't know exactly why i can manipulate signals or why a monopole length part way between the original sigma and original vector works best in our tests,

all that bs about lossy gammas and higher takeoff angle than a 5/8wave was and still is technobull,

i picked up my astroplane this evening, a Big THANK YOU to Henry and mark, if it had not been for those guys i doubt any of us would have got our antennas,

i have not opened the box yet, it looks good sat beside my NOS avanti saturn,
takes me back to when i was a lad opening my first sigma4 & assembling it in my mums room ,
then realising i had to take it apart again to get it outside,

i will let you know what i think of the astroplane when i get it or my homebrew up in the air at the same tip height as the i-10k on the same pole same coax,
It ain't over till the fat lady sings

thanks for doing the astro models,
can you put the cursor on the lower lobe or does it always go on the highest gain lobe in EZNEC ?.

 

[Marconi]

the sigma4 does provide more signal at low angles than any 5.8wave when mounted on the same pole,

At some point I posted all of my antenna models at 32' feet over average Earth in a PDF file. I first put them in descending order of rank as to best gain and angle. This will confirm what my Eznec models, right or wrong, have generally shown for some time.

I probably have worked on many of these models and made changes that improved the model, and could have either resulted in more or a bit less gain. The only one I know for sure is the Vector 4000, which ended up with less gain, and I moved it in the file as a result.

See the PDF here in my post #1 noted as "View Attachment":
http://www.worldwidedx.com/threads/take-off-patterns-for-cb-antennas-we-use.158801/

IMO, there is not enough difference here to really matter just using our radio to tell.

it looks likely it may not do it as i first imagined and for sure the increased height of current maxima is a vital part of the equation,

I'm not sure what your point is here, but I guess you'll explain in due course.

i still don't know exactly why i can manipulate signals or why a monopole length part way between the original sigma and original vector works best in our tests,

Bob, I think I studied this idea with my models sometime back, but I don't remember exactly what I saw in the process, and I'm also not sure how Sirio's increasing the radial length played into all the considerations for a longer Vector either. I think their issue in changing to the New Vector 4000 design was to make the antenna a bit shorter without sacrificing any gain...in order to help improve the durability of the product. So, maybe they did give up a little gain. But I wonder how much gain could it be? All I know is I cannot make my model show the gain that Sirio reports for their New Vector 4000, in free space or over real Earth.

I can make my Sigma 4 show a lot better gain and angle if I cheat however...and maybe one day I will show how that is possible.

i will let you know what i think of the astroplane when i get it or my homebrew up in the air at the same tip height as the i-10k on the same pole same coax,
It ain't over till the fat lady sings

Fair enough Bob.

BTW Bob, with some of my contacts this past weekend...I would turn my power down to less than 5 watts and nobody was ever the wiser. I do not recall loosing a single contact as a result, but I do remember one guy that had no signal and I could only read him on my NTO...which at times was noticeable quieter.

thanks for doing the astro models,
can you put the cursor on the lower lobe or does it always go on the highest gain lobe in EZNEC ?.

Yes Bob, the cursor always pops up at the maximum angle given! I attached the pattern with the cursor moved to the maximum low angle which shows a fraction less gain.

 

[bob85]

maybe its not absolute gain that's important eddie, the angles of interest to me are the lower lobes, what gives best results at low angles,
you remember the claim that a 5/8 has the lowest takeoff angle, and me not agreeing with that based on how far i can talk local on the hybrid vs my 5/8waves,

i sort of remember your list of models but not the details,
we have an issue with what your models show not agreeing with what me and Donald see in our tests when the monopole is extended beyond 3/4wave but not as long as 7/8wave, im still not sure about why that is,

all best are off if i have skip or im experiencing multipath flutter
the signals must be stable imho,

even airplanes cause significant flutter between me and a buddy a few miles away, peaks and troughs in his signal and changes in receiver quieting that vary in rate of repetition as the plane gets closer to me,
i can tell him a plane is going over his house way before i can hear it,
it stops when the plane is about midway between us and starts again as it gets closer to me, he hears & sees the same thing,

i have been presented with a couple of ideas about why raising a 1/2wave does not seem to make it equal to my hybrid when the smart guys say it should and they make sense to me,
unfortunately i don't have a decent 1/2wave endfed with low loss matching that i could isolate to test the idea,

i do remember years ago comparing a99 against a sirio 2012 and stock sigma on a pneumatic mast at my parents,
the a99 and sirio 2012 were about equal and the sigma 1.5 s-units higher on a uniden cb,

im hoping to get some more input.

 

[Marconi]

maybe its not absolute gain that's important eddie, the angles of interest to me are the lower lobes, what gives best results at low angles,
you remember the claim that a 5/8 has the lowest takeoff angle, and me not agreeing with that based on how far i can talk local on the hybrid vs my 5/8waves,

I agree Bob, that absolute gain is likely not likely what matter as much as we think, but we do use it as a gauge for comparisons even if we don't test under idea situations.

Until I could model and see what a science type application might show for gain, about all I could do otherwise, would be to get my gain information off of Joe Gunn's website or the like. However, I still can't tell, or even get close to telling what the actual gain or angle is for any of my antennas. I do try and use a little common sense though and I tend to read a bit regarding what others have to say on the subject.

You and I both know that my models show and have shown that the S4/NV4K antenna should show more gain at a bit lower angle than a 1/4, 1/2, or 5/8 wavelength vertical antenna. IMO, science also shows this to be a fact. The only thing I don't see...is the amount of differences that most report.

i sort of remember your list of models but not the details,
we have an issue with what your models show not agreeing with what me and Donald see in our tests when the monopole is extended beyond 3/4wave but not as long as 7/8wave, im still not sure about why that is,

I think I will make a new effort to see how Eznec predicts this now...as I think I know a bit more about modeling in Eznec now and might be able to consider more in the process. At the very least I know now how to make sure my models are consistent in setting within the 500 segments available to me with my version of Eznec.

all best are off if i have skip or im experiencing multipath flutter the signals must be stable imho,

I never tested during DX unless I wanted to make spme comparisons for some special reasons. I did it mostly, because most of my old radio buddies...went into hibernation during previous DX periods and I have no body dependable to check signals with.

even airplanes cause significant flutter between me and a buddy a few miles away, peaks and troughs in his signal and changes in receiver quieting that vary in rate of repetition as the plane gets closer to me,
i can tell him a plane is going over his house way before i can hear it,
it stops when the plane is about midway between us and starts again as it gets closer to me, he hears & sees the same thing,

i have been presented with a couple of ideas about why raising a 1/2wave does not seem to make it equal to my hybrid when the smart guys say it should and they make sense to me,
unfortunately i don't have a decent 1/2wave endfed with low loss matching that i could isolate to test the idea,

Well, even if the 1/2 wave you have shows to be less efficient due to a lossy matcher...it might still demonstrate some ideas for the difference you're looking for...as compared to your Vector Hybrid on raising to some discrete heights. IMO, efficiency is one thing, but effectiveness is another and can produce completely different results. IMO, tt depends a lot on what we're looking for.

I've heard this story before Bob. You just made a similar comment about what some claim regarding the use of a gamma matcher. How do we tell if a matching system is lossy or efficient or not? I think, at best, we can get a sense for effectiveness...but that is about it as CB'r go.

i do remember years ago comparing a99 against a sirio 2012 and stock sigma on a pneumatic mast at my parents,
the a99 and sirio 2012 were about equal and the sigma 1.5 s-units higher on a uniden cb,

im hoping to get some more input.

If the ratio of db's to Sunits is truly 6 db's like most report...then I find it had to believe this claim, but instead consider this much difference has more to do with some natural condition that makes the difference noted. IMO, 9 db's is a big difference. Plus we constantly hear that radio meters are almost as useless as tits on a boar hog at giving us accurate information.

Bob, I'm sorry, but all my days in experiences in radio have shown me that much of the differences seen and reported in comparing radio operations...is much less of a difference than typically reported.

I guess I'm just too cynical to believe much anymore. I still believe most folks see what they claim, but common senses sometimes appears to be absent in my eyes, so my cynicism is not meant to be personal.

Good luck with your new work on your station. After several years feeling like crap most of the time...I too have a new spirit to get back into some antenna work again. The only problem is today...I find few folks on the air to test with, and when local traffic begins to dominate again...I don't look for CB to resume as in the past...with plenty of signals to consider in my hobby.

Good luck in you efforts for more input Bob,

Keep us posted.

 

[Marconi]

Bob, could you do me a favor and give me the precise dimensions for you Avanti Astro Plane? See image below.

I just rechecked my Avanti model, and I found I had some minor mistakes in the dimensions and it has made a noticeable difference in performance results.

All I have for this version of the original A/P is a schematic I got off of the Internet in mm, and I am not sure about the accuracy.

I had the mounting bracket set at 3" x 6" and that is apparently not correct and that dimension too...makes a noticeable difference.

You can use mm or inches.

I need the dimensions, length and diameter, for all the individual elements of course. If you will get me the dimension for the main bracket width from center of element to center of element...and then the physical width of the bracket overall. Here is a image you can use if you like.

Dimensions for the bracket and angles for the radials are very important to this model as you understand from the Patent. They are also just as important as the similar dimension on the Sigma4, radial bracket at the bottom of the antenna and the angle of the radials relative to the mast at bottom and top.

I also need the precise dimension from the center of the radial to the center of the boom where the bottom radial elements connects to the top radial element. This is so I can get the proper bow for the radials. Tell me if the radials are made up of one piece of tubing or two pieces for the original. If the radials are made of two pieces of tubing then what are their diameters too.

I also need to know if can confirm that the center of radial to center of radial...where the radials hook on to the hoop is = <>30" or not. My hoop on my Old Top One is set at 30" inches, but the actual distance for the radials, center to center, is probably what is most important.

 

[bob85]

1 s-unit been equal to 6db is not even close to correct on any cb or ham i ever owned eddie,
if that were true we would never see much difference in antennas,
the laziest meter of any of my radios is my jrc that is very close to 3db per s-unit,
i upset folk when they test amplifiers and i don't report signal 3 jumping to s9+10db,
if you want flowers ask somebody using a yaesu ft847 for a signal check,

this vid is much closer to what you can expect from a uniden cb



we will have to agree to disagree on signal reports, when i tested my imax against the i-10k one friend saw 1.5 s-units on a legal uk uniden 200 while another friend saw a much larger drop on a midland allan cobra 148 export clone and the reverse when i swapped back to the 10k, same pole/coax/radio at my end.

clearly there is not that much difference in gain but there that much difference in signal where my antennas are used,
im not testing in my dads field like i did back in the day.

 

[Marconi]

1 s-unit been equal to 6db is not even close to correct on any cb or ham i ever owned eddie,
if that were true we would never see much difference in antennas,
the laziest meter of any of my radios is my jrc that is very close to 3db per s-unit,
i upset folk when they test amplifiers and i don't report signal 3 jumping to s9+10db,
if you want flowers ask somebody using a yaesu ft847 for a signal check,

this vid is much closer to what you can expect from a uniden cb



we will have to agree to disagree on signal reports, when i tested my imax against the i-10k one friend saw 1.5 s-units on a legal uk uniden 200 while another friend saw a much larger drop on a midland allan cobra 148 export clone and the reverse when i swapped back to the 10k, same pole/coax/radio at my end.

clearly there is not that much difference in gain but there that much difference in signal where my antennas are used,
im not testing in my dads field like i did back in the day.

Thanks for the info and the video Bob.

I remember a long time ago when you presented that idea to me, and I think I realized immediately that what you were saying was true and it explained a lot...for what I had seen in my experience and could not explain.

I have always been on your side buddy...even when I might have disagreed. I know I can depend on your understanding...even when I have reported what I see that doesn't agree with what you see.

The following comments are not for you Bob, but for others who, IMO, sometimes don't always understand. I mostly have always had questions, and this is what rubs some folks the wrong way...when I ask questions.

I don't have to call folks a liar, which many think I do when I give my point of view and would in turn give anybody the chance to voice their own opinion. Just because I disagree or ask questions of somebody...doesn't mean I hate and don't want to consider what other folks think.

Thanks for the video and you words.