How high should I go?

[Marconi]

1 and 1/2 wl has been determined to be the best for working DX.

On 11 meters that is around 54'.

50' of tower and your mast pipe out the top to mount the yagi,, 3 element is a good choice, good forward gain, decent F/B and a lot of bandwidth.

Mount the IMAX above the yagi as previously mentioned in other posts.


That antenna system is a good all around system if put together correctly.

Captain Kilowatt has a thread about putting up tower with pictures of how it is to be done. Good info there.

Hey Wavrider, do you have a link that discusses the height of 54' feet as being the best height?

I'm doing a few Eznec5 models, raising the antenna 1' foot at a time, and comparing results. I find that raising doesn't always improve the gain and angle as in a linear type curve, it varies and there seems to be some consistent change for the worst around 20' & 38', at least on my Starduster model. My I-10K, doesn't seem to show such at the same heights, but there may be other heights were it too doesn't work too well.

It seems to me that different antennas seem to respond differently on raising. I base this not exclusively on the gain and angle, but additionally on how the currents flow on the supporting mast, which really seems to ill-affect the pattern at some heights.

So I watch the currents real close too.

Again, do you have a link to such a discussion on 54' feet being the best height, or did that come from you own experiences? If you have a link, could you post it?

 

[Marconi]

how was 54 ft determined to be the best height .
would performance be decreased by going to 75 or 100 ft ?

I'm not yet totally sure about all antennas responding the same BM, or whether these models represent what happens in the Real World, but my Starduster model at the heights you note in your question produce the classic example of what I posted to Wavrider about up above.

Check out the current on the mast in red and compare. IMO, it is these currents that produce the unproductive RF in the pattern, that is basically wasted. The gain and angles are both good, but the 75' footer could be better at some other height, and possibly not loss much gain or angle. The 100' foot height might show improvement at some other height very near 100' feet too.

View attachment Starduster 75' - 100'.pdf

 

[Robb]

http://radio.n0gw.net/radio12.pdf

 

[gamegetter]

coincidentally

50-60 feet is what I need to clear all the tall trees by my house and allow the antenna to see the 'horizon', i have a tower in the planning. but i been using 20-30' feet and enjoying what i can.

to the poster I would say get it as high as you practically can, if you are not challenged by alot of trees or buildings around and can see the horizon, you should get alot of enjoyment out of it until you get more serious and can plan some of the taller heights mentioned here.

important thing is to start enjoying it and see if you are going to stay in the hobby. then fiddle with it some more

just my 2 pennies worth. good day, good luck and for lack of a better word, erect antenna's safely.

 

[Captain Kilowatt]

IMHO the opinion that 54 feet is the best is taking into account the performance at that height as well as the effort and expense to get the antenna at that height. IOW the best compromise. No single height will be the best height EVER for any band or antenna however there is always a best compromise. The difference of 10 feet or so from 54 to 64 is moot while the difference from 20 to 30 may be more dramatic especially it it puts the antenna over the top of surrounding objects that it could not clear at 20 feet.

 

[Marconi]

BM, here is what Eznec5 shows for my I-10K for the difference in 50' and 54' in height. The I-10K is a much more complicated antenna to model than the Starduster. I have included the matcher as well so that I could get some control over the bad match the 5/8 wave shows without a matcher.

If these are even close and you can get your I-10K up this high, would it be worth a try for somebody to check, and see if it's true in the real World?

Again, check out the currents in red, and compare the pattern differences, while the match remains still pretty good. Again the increased currents on the mast pushed the high lobe up even higher and is wasting RF up there.

View attachment I-10K 50' - 54' feet.pdf

 

[Robb]

We possibly may be moving in a month or two. So I want to start with a fresh antenna. I currently run a Imax 2000 on a 30ft push up pole. Some people say "you can never get high enough" some people say 1st ground wave is best. Probably the Maco 3 element beam will be my next antenna. Should I use my 30ft push up pole or put up about a 60 ft tower? The Imax just doesn't satisfy me. I think the most fun is talking long ground waves (50-100mi). Would the beam be for me?

Putting up an antenna must also include certain safety considerations. FYI - even adults still get killed when an antenna installation goes wrong. If a metal antenna should fall on a power wire - and one is still holding on to any part of it - 'instant electrocution'. This is no joke.

If you want to be the best station in your area; then height is king. Not necessarily power. Just remember, that if you run a dirty amp and the antenna is ~54 feet up, you may splatter over a greater distance.

A beam is a really fun antenna. Won't even kid you about it. I use and prefer the beam. I've talked all over the world (literally) in the last six months with less than 100 watts and just a four element horizontal ('Yagi') beam - at a height of 35 ft/1 wave length (one wavelength of the 11 meter band/CB band is 36 feet). You can read all about it here:

http://www.worldwidedx.com/dx-contacts/124847-west-coast-california-dx-contacts-today.html

I can assure you that no on talking serious skip will use a dirty amp. Too hard to understand someone if they are garbled. They don't use AM either; just SSB. Most successful skip talkers will use 100 watts or less and let the DX/ionospheric conditions and their antennas make it happen. Optimizing the antenna is absolutely essential in this regard.

 

[BOOTY MONSTER]

"I can assure you that no on talking serious skip will use a dirty amp. Too hard to understand someone if they are garbled."

ever been on channel 6

 

[wavrider]

QST magazine either October or November 2011 goes into great detail on how that 1 1/2 wl came about and actually explains tests conducted and how it was measured.

I think you may have to Be a member of the ARRL to get it online not sure. I let my membership expire.

I will hunt another link I think I have it saved somewhere.

Hey Wavrider, do you have a link that discusses the height of 54' feet as being the best height?

I'm doing a few Eznec5 models, raising the antenna 1' foot at a time, and comparing results. I find that raising doesn't always improve the gain and angle as in a linear type curve, it varies and there seems to be some consistent change for the worst around 20' & 38', at least on my Starduster model. My I-10K, doesn't seem to show such at the same heights, but there may be other heights were it too doesn't work too well.

It seems to me that different antennas seem to respond differently on raising. I base this not exclusively on the gain and angle, but additionally on how the currents flow on the supporting mast, which really seems to ill-affect the pattern at some heights.

So I watch the currents real close too.

Again, do you have a link to such a discussion on 54' feet being the best height, or did that come from you own experiences? If you have a link, could you post it?

 

[wavrider]

http://www.arrl.org/files/file/QEX_Next_Issue/May-Jun_2011/QEX_5_11_Siwiak.pdf

Sort of technical but there are graphs.

Summary and conclusion shows the WL height

 

[Marconi]

http://www.arrl.org/files/file/QEX_Next_Issue/May-Jun_2011/QEX_5_11_Siwiak.pdf

Sort of technical but there are graphs.

Summary and conclusion shows the WL height

The report is interesting.