Homer's Qv4k

[HomerBB]

My previous experience with This antenna was such that I had better performance near the ground with it than any other monopole antenna that low. I speculated that it was due to it being so tall of itself. You may find that to be true. Wait and see.

I have wondered also if it was because of the collinear effect of the 1/4 wave section below the 5/8 wave. i do not know and am not learned enough to figure that piece out, yet.

 

[BOOTY MONSTER]

i think i recall bob85 saying something about the design making it less sensitive to surrounding structures or objects . i'm guessing the extra length compared to other antennas at the feed point doesn't hurt either . i hope ill have mine finished this weekend .

 

[hotrod]

My previous experience with This antenna was such that I had better performance near the ground with it than any other monopole antenna that low. I speculated that it was due to it being so tall of itself. You may find that to be true. Wait and see.

I have wondered also if it was because of the collinear effect of the 1/4 wave section below the 5/8 wave. i do not know and am not learned enough to figure that piece out, yet.

question is are you better off with he v4k mounted low or
something like a sirio top one mounted higher ablove structures and stuff

 

[HomerBB]

i think i recall bob85 saying something about the design making it less sensitive to surrounding structures or objects . i'm guessing the extra length compared to other antennas at the feed point doesn't hurt either . i hope ill have mine finished this weekend .

I'm really looking forward to you getting it up and running. Yours will be the only other homebrew V4k I know of. There are likely others, but I would like to know what your results are from the work you've done.

 

[HomerBB]

question is are you better off with he v4k mounted low or
something like a sirio top one mounted higher ablove structures and stuff

In my opinion, hotrod, the great length of the v4k makes it very desirable if low is your only option. Based on which model one puts in the air, the length of the antenna alone places it 3/4 of a wavelength at the top over whatever pole it's on. I haven't run a top one, but I did run the Astroplane original and found it a superb antenna doing its best higher up.

That said, if getting one high up is no problem, then the V4k would be the best in any case.

When I first ran my Qv4k it was not too good I thought, just fair, so i went back over it to improve it. I mounted the Astroplane as high as I could get it and it out shone my Qv4k. I am beginning to believe the newer Qv4k will out perform my Astroplane. I will have to give it more time to be sure.

 

[hotrod]

In my opinion, hotrod, the great length of the v4k makes it very desirable if low is your only option. Based on which model one puts in the air, the length of the antenna alone places it 3/4 of a wavelength at the top over whatever pole it's on. I haven't run a top one, but I did run the Astroplane original and found it a superb antenna doing its best higher up.

That said, if getting one high up is no problem, then the V4k would be the best in any case.

When I first ran my Qv4k it was not too good I thought, just fair, so i went back over it to improve it. I mounted the Astroplane as high as I could get it and it out shone my Qv4k. I am beginning to believe the newer Qv4k will out perform my Astroplane. I will have to give it more time to be sure.

i ask cause it would be difficult for me to keep up a 29 foot long antenna up on
a 30 pklus ft. tower/mast. plus i get alot of wind somedays
on the other hand i could easy raise a lil 12 foot antenna up on a 30 ft. tower/mast
BUT would it be better than the longer than v4k mounted low?

 

[HomerBB]

i ask cause it would be difficult for me to keep up a 29 foot long antenna up on
a 30 pklus ft. tower/mast. plus i get alot of wind somedays
on the other hand i could easy raise a lil 12 foot antenna up on a 30 ft. tower/mast
BUT would it be better than the longer than v4k mounted low?

The question that might first need to be answered is whether you can get the V4k higher than 13 or more feet at the feed point.

30' mast plus 12' Astroplane/Top One = 42 feet to top.
13' mast plus 29' V4k = 42 feet to top.

It is believed the Astroplane radiates high up in the antenna.
It is thought the V4k also radites the most significant part of its sigmnal from the upper part of the antenna.

If these things are so, it is a matter of how high you can get each of the antennas to give one of the other the advantage.

Which would I do?
The V4k as high as I could get it above 13'.

 

[hotrod]

The question that might first need to be answered is whether you can get the V4k higher than 13 or more feet at the feed point.

30' mast plus 12' Astroplane/Top One = 42 feet to top.
13' mast plus 29' V4k = 42 feet to top.

It is believed the Astroplane radiates high up in the antenna.
It is thought the V4k also radites the most significant part of its sigmnal from the upper part of the antenna.

If these things are so, it is a matter of how high you can get each of the antennas to give one of the other the advantage.

Which would I do?
The V4k as high as I could get it above 13'.

i could easily get the top one up higher and feel safe doing it
the v4k at 29 ft by itself 13 ft mast would most likely be about it

 

[gamegetter]

greetings hr

i would try both and see which one accomplishes what i need it to do for my particular conditions setup and or etc.

there really is only one way to find out which one is going to work best for you and that is to try them. there are so many variable that can affect your set up and trying them out is going to be best.

if you set up the 4k and it works best for you but your neighbors are complaining or you live in a restricted neighborhood, then try the astroplane it is about all you can do.

sometimes these things take a little elbow grease to figure out what is best for you. If you try both it would be great information to share with the forum as to why one worked better for you. hope this helps out, i know it's not what you wanted to hear but it is what it is. best of luck.

 

[Shockwave]

Height is going to help with all of your line of sight contacts both local and out to over 100 miles in some cases. If you're stuck with having to mount an 11 meter antenna less then 15 feet above ground, the Vector is your best option by far. Do not misunderstand this as meaning the Vector works better on the ground then it does elevated. The advantage is the coaxial cone on the Vector provides some isolation to the affects of other reflective objects in its field. Including ground reflections that may be closer then desired.

If you can't get the Vector up on your 30 foot mast and you run 1/2 KW or less, invest in the Gain-Master. This will most likely provide you with the most range with the mounting options you have available. The Astroplane is a great antenna for its size but it was also specially designed to be compact and uses the mast as part of the antenna. This will surely create more RFI then the Gain-Master.

 

[Marconi]

The question that might first need to be answered is whether you can get the V4k higher than 13 or more feet at the feed point.

30' mast plus 12' Astroplane/Top One = 42 feet to top.
13' mast plus 29' V4k = 42 feet to top.

It is believed the Astroplane radiates high up in the antenna.
It is thought the V4k also radites the most significant part of its sigmnal from the upper part of the antenna.

If these things are so, it is a matter of how high you can get each of the antennas to give one of the other the advantage.

Which would I do?
The V4k as high as I could get it above 13'.

Homer here are some pattern overlays for my Sigma4 at different heights. I just took my Sigma 4 model and raised put it at 10' then raised it up to see what happened. It is hard to see the red, but it is basically the same as the 40' high default Sigma4 I published a while back. Red, dark blue, and black appear to be the same at the maximum gain and all about the same angle. I can account for the 10' height showing less gain maybe, but I can't explain why 36' shows less gain. This is all over average soil.

Also note what happens with the 10' foot pattern right above the lowest lobe, it shows more gain at a bit higher angle. So, if the near-by locals signals are within this angle range, it might account for their showing stronger signals.

View attachment Sigma 4 at different heights .pdf

 

[HomerBB]

Very good overlay. It seems to me if I m reading it right the 10' elevation shows what I experienced. There is a strong secondary lobe which I think would have accounted for the strong ears to stations locally and out to 25 miles.

Can you do a 5/8 with 4 9' radials the same way?

 

[Marconi]

Very good overlay. It seems to me if I m reading it right the 10' elevation shows what I experienced. There is a strong secondary lobe which I think would have accounted for the strong ears to stations locally and out to 25 miles.

Can you do a 5/8 with 4 9' radials the same way?

Yes I think you're right, I just added that to my remarks.

I have my model of the I-10K with horizontal radials, I could shorten the up a bit and I will do the same with an overlay. I think you are curious about the pattern affect, right?

 

[HomerBB]

Yes I think you're right, I just added that to my remarks.

I have my model of the I-10K with horizontal radials, I could shorten the up a bit and I will do the same with an overlay. I think you are curious about the pattern affect, right?

Absolutely.

 

[Marconi]

Here is your model of the 5/8 wave with short radials vs. standard 1/4 wavelength. Remember this 5/8 was not an attempt to model the I-10K, I just made it at 22.5' long with 8.5' radials on a 40' foot mast.

The first three pages are the default I-10K, and the rest is info for it with shortened radials. Besides the bad pattern affect notice the heavy curren flows on the mast with the shortened radials. Maybe manufactures add shortened radials to increase the local signals with the higher lobe as you noted earlier regarding my Sigma4 model. I can't explain why the overlay also seems to indicate that both models produce the same gain. That is not supported by the details however.

View attachment Homers 5_8 wave with short radials.pdf