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Vector 4000 Remake

Well now, Marconi, I have no idea what is going on.

Clearly I have missed something along the way.

I will say that I have not been playing with you in any way, nor attempted to be cute.
As for the more or less, in the two previous major threads regarding this antenna on the forum there were suggested dimensions for the Gamma Match of considerably different lengths. I had finally taken them all and built one of virtually every suggested size until the Dimensions provided on the graphic showed up. On the graphic it called for a tube of .512" diameter. I used one that was as near as I could get - 1/2" ID. etc. So there in lay the more or less I was referring to. I attempted to reuse that same Gamma match for this antenna. Although I had gone with dimensions for the lengths of all parts of the antenna I can not exactly duplicate the diameters and exact tapers of all the tubes, so with the materials at hand I replicated every thing I could as near as I could. There in lies the more or less. I put the Gamma that I had used before on the other antenna on this antenna, and like the previous antenna, the SWR meter showed me exactly what I had seen on the other - a wide banded very low SWR matched antenna. I did not possess an analyzer back then, and had no idea what the true health of that antenna was until I got one. When I did get one I stood the Sigma IV in the air and no amount of adjustment with the Gamma in use would give me any good results. You may or may not recall I said this to you in an email, and over the phone. The same thing happened when I used that Gamma Match with this antenna although I had put the only dimensions I could exactly match into the antenna - lengths - with the materials I have in my possession, or available in this small town on my limited budget. I could not get a good tune aside from a low SWR. That is why I remade the Gamma to the original specs but with greater diameters. I was trying to get a Gamma on the antenna that would actually address the issue of resonance where I needed the antenna to tune, and provide a decent match.

Following the precedents you asked for I reported my findings at this point. I answered your questions exactly as I thought the only answers I had were. The Gamma provided the closest match using only the proper length of coax advised by MFJ when tuning an antenna, whereas using the longer coax also did as MFJ said it would do - give miscalculated data.
The only question I could find I may not of directly answered was what did the use of the dummy load suggest to me with respect to the antenna results. The answer is,

1. I needed to do more work on the antenna, and

2. The dummy load is not an antenna so it will always be happy no matter what coax length I use so long as the coax is good.

I only mentioned the dummy load to establish that both coaxes I was using were not lacking integrity - they were known good feedlines.

I hope you are feeling well. I regret the challenges you are facing at this point that keep you from being able to do what you so enjoy.
I do appreciate and value your participation.

I only put the contact in the post because for me, when all is said and done, no matter the opinions of those who care or not for this particular antenna, what it does for me in the air will be the ultimate test of its value. In my very first post on the thread I established that I would be running comparisons of this antenna against the ultimate antenna baseline for comparison - the dipole. The dipole is also mounted vertically with a bottom height for both antennas of 27.5'.

Homer
 
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Perhaps a written track on the last MFJ readings will help:


------ E1/2 wave jumper ----------------------- Feedline in the shack
SWR
2.0 -- 28.374 --- R75 -- X19 ------------------- 28.569 --- R35 -- X18
1.5 -- 27.960 --- R56 -- X21 ------------------- 27.942 --- R86 -- X0
1.1 -------------------------------------------- 27.385 --- R57 -- X4
1.0 -- 27.564 --- R54 -- X0 ------------------------------------------
1.0 -- 27.387 --- R56 -- X0 ------------------------------------------
1.5 -- 26.893 --- R72 -- X14 ------------------- 26.509 --- R56 -- X23
2.0 -- 26.515 --- R103 - X0 -------------------- 25.957 --- R127 - X0
 
HOMERBB,, looks impressive and if the performance is as good as the appearance it should work great.

Thanks for the pics.
 
Thanks, wavrider.
I am hoping it is a winner.
The reason I have returned to this antenna, a thing I did not think I would do, is because I believed there may have been a reason in the structural design of my last homebrew, a Sigma IV, that resulted in poor analyzer readings.
I had stated the same to Marconi in some emails, and in phone conversations, as well as on a thread here on the forum. I thought this fine antenna design deserved another shot for a run at it on the MFJ-259b.
I have come to the conclusion that there are simple small details on this antenna that can have potentially large impact on its tuning and perhaps its performance.
I was looking in particular at the stand-off from the vertical radiator at the bottom of the radials. In my previous builds I had simply begun radials at a slope away from the vertical without any standoff. I had also used shorter raidials than the specs on the New Vector 4000 called for on the OEM model. Another potential issue I wanted to face and set aside was the fact that I was incorporating materials like aluminum coated fiberglass and CPVC into the antenna, and hoped to eradicate any argument I was having with myself that those techniques might have some impact.
The latest posted readings from the analyzer indicate that I have been moving in the right direction.
As Marconi suggested, finding a baseline for the antenna that is acceptable and working from there is/was my goal. I may be there now but hoped for some input to that from some here on the forum. To resolve the question of the potential impact of the stand off on the radials I will have to remove them and see where the match lands; does it move or remain constant . . .
We shall see if interest in this endeavor holds long enough to figure it out.
Thanks for looking in and posting.
 
Latest photos. I moved the X strap that supports the radials in position upward . It wasn't long enough to go any higher until I modified it.

V40573b_zps7a966254.jpg
V40572_zps1d31b167.jpg
 
I have made a few comparisons of this one, the Q2v4k, to the dipole with both having a bottom height of 27.5'; the Q2v4k (Quasi 2 Vector 4000 Homebrew) has handily beaten out the humble, but nimble, dipole in every case except those within 2 miles of me.

I am seeing and hearing perceptible differences between them, and reports are confirming this for me by some with whom I am in contact.

In the DX melee it is difficult to get reports, but I have managed some on the upper quieter channels with the Q2v4k reigning chief over the dipole by at least 1 to 2 S units. We know DX is the great equalizer.

On the local scene when DX is not ruling the band I have enjoyed better results with the Q2v4k as well.

Rogers, AR to Jane, MO ---- 20 miles as if in the neighborhood.

Rogers, AR to Berryville, AR ---- 31 miles, giving him 7 - 9 with him sounding as if he were within the 20 mile range.

Rogers, AR to Wyandotte, OK ---- 47 miles through the Ozarks with clearly readable transmissions each way. He sounded as if he were half that distance. He disappeared when I switched to the dipole.

I can not prove this, but I sincerely believe this antenna does as it is purported to do, it lays the signal much nearer the horizon than other omnis.

In every case I was working with 150 watts PEP.

I an hoping to catch some of those stations that work AM out in the Branson , MO area A 68 mile trip though some of our most rugged terrain, and beyond that that I have not heard since the Qv4k(my original homebrew) went on to another home.

This one has required more patience as I have striven to make it a permanent build since the beginning. It is not a soft line and sash cord build, no duct tape either!

Listen up for me, I'll be hunting you.
 
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that's the kind of result we see here when comparing antennas homer,
i expect the same result but not the same magnitude of advantage when comparing a properly dialed in vector to any other vertical on the same pole not counting the big-mac.

good work;)
 
I couldn't resist pointing out that if the cone did not radiate, the gain Homer is seeing over a half wave dipole would not be possible. Without the cone, the Sigma is just an end fed 1/2 wave. With the cone it's a half wave over a 1/4 wave and phased constructively.
 
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I couldn't resist pointing out that if the cone did not radiate, the gain Homer is seeing over a half wave dipole would not be possible. Without the cone, the Sigma is just an end fed 1/2 wave. With the cone it's a half wave over a 1/4 wave and phased constructively.

why wouldn't it be a 3/4 wavelength (+) vertical without the basket ? not that 3/4 would be better since FWIU beyond .64 WL the TOA starts being dominated by higher higher angled lobes .
and thanks for another excellent thread on this type of antenna . i'm looking forward to getting mine back up hopefully .
 
I am convinced, Shockwave.
I have been a friend of this antenna since the first I built. This one differs from that with respect to the materials employed in each, and because I never had the opportunity to build the former Vector 4k nor the Sigma IV using an analyzer.
Having the dipole up simultaneously for comparison is a bonus, too.
I know there is debate about comparing antennas on two different feedlines and masts, but it is what it is, and I am more interested in my experience between the two than measuring differences scientifically. It works.
 
why wouldn't it be a 3/4 wavelength (+) vertical without the basket ? not that 3/4 would be better since FWIU beyond .64 WL the TOA starts being dominated by higher higher angled lobes .
and thanks for another excellent thread on this type of antenna . i'm looking forward to getting mine back up hopefully .

I think this is just a matter of clear wording. I was considering the cone and the vertical section inside the cone being removed to form a simple 1/2 wave end fed. Indeed, if you just remove the cone alone you will have a 3/4 wave with severe inverse currents in the base. At that point the 1/2 wave end fed would easily outperform it.
 
I couldn't resist pointing out that if the cone did not radiate, the gain Homer is seeing over a half wave dipole would not be possible. Without the cone, the Sigma is just an end fed 1/2 wave. With the cone it's a half wave over a 1/4 wave and phased constructively.

Donald would it be possible to show the cst plots of the old vector 5/8 over a 1/4 wave against the what i would imagine are similar plots of the 1/2 wave over a 1/4 wave new vector / sigma 4,

i'm curious to see what effect the extra 1/8 wave radiator had on the phasing and why sirio returned to the 1/2 over 1/4 wave format, i'm assuming it was to strengthen the antenna but i'm curious to know what the trade off was, it wouldn't surprise me if the new vector lost an insignificant amount of performance over the old vector in favour of stronger construction.
 
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Donald would it be possible to show the cst plots of the old vector 5/8 over a 1/4 wave against the what i would imagine are similar plots of the 1/2 wave over a 1/4 wave new vector / sigma 4,

i'm curious to see what effect the extra 1/8 wave radiator had on the phasing and why sirio returned to the 1/2 over 1/4 wave format, i'm assuming it was to strengthen the antenna but i'm curious to know what the trade off was, it wouldn't surprise me if the new vector lost an insignificant amount of performance over the old vector in favour of stronger construction.

If I had them, I would share them. I suggest that the top of the antenna would perform the same as the difference between a 1/2 wave and a 5/8 wave. Expect a little inverse current to appear on the exposed vertical radiator as a result of the longer wavelength. All I can say for sure is the .82 wavelength I use puts more gain on the horizon then either the 3/4 wave or the 7/8 wave. I've tested this at least a dozen times in the field over the last decade and consistently come up with the same result.
 
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