vertical and horizontal transmission at same time

[Captain Kilowatt]

news to me. Read #6 "The severe aperture interference also causes the antenna to exhibit a high angle of radiation. It would be easier (and cheaper) to elevate the antenna far enough so that the aperture does not touch the ground. "

I would hardly call one hams opinion a credible resource. :laugh: I prefer to use the NAB Engineering Handbook for such info as well as the experience of thousands of hams which well document the fact that a ground mounted vertical antenna with a proper ground plane IS indeed an excellent DX antenna. John Devoldere, ON4UN has written several books on low band DX'ing and has shown that a vertical antenna can be a formidable opponent.

 

[Kamikaze]

So this has morphed from a CB antenna thread to a low band vertical thread....

 

[wavrider]

So this has morphed from a CB antenna thread to a low band vertical thread....

I do not know if it has morphed from an CB antenna thread to low band vertical thread.

What is the difference, if any, of a CB antenna and any other antenna for the HF frequencies? Besides the electrical length and frequency of operation.

Antenna theory is antenna theory, performance on the other hand is drastically effected by the installation of any antenna. Whether it is vertical or horizontal.

This thread has a wealth of information from the members who contributed to the posts irregardless of the title of the thread.

 

[slateblue]

Hiya

The beauty with radio is our ability to dabble into the EM spectrum which is known to be an element of the building blocks and structure of the known universe.......we use this to communicate with and, perhaps make little experiments. Although, we think from our personal perspectives that our data and theories are exact, within the arena we exist many different superpositions can occur so we should be open to these differences and, not try to tie everything down to what our instincts tell us about what we feel and see.

This is an adventure but, all being equal, I would go with a Vertical polarised Quad, as I use my self with my limited QTH, which provides good local coverage and DX.

My feelings are that, verticals that are to big are just a little phallic in nature and, perhaps, this may be why some peeps get a little exited about the subject!:blink:

Im sure Freud would have a field-day......:bdh: .....have fun.....

 

[W5LZ]

 

[Henry HPSD]

Guys,

With all do respect, although the math is equal...there is a major difference between low bands (1.8Mhz/3.5Mhz) and the band we are on.

It all has to do with at what angle the propagation comes in.
For real DX we must have a low take off angle.

In order to get a low take off angle using a horizontal antenna the antenna must be at least a halve wave from the ground, preverbly higher.
To make contacts outside your continent a heigth exceeding a full wave length is recommended and also in this case..preferbly higher.

Now for 11 meters this is mechanical wise not a issue.
For low bands this is...(thats a major difference!)
Yes, i know there are guys running beams on 160/80 and with that, we have exactly our point! Please bare in mind, they beat any vertical system easily.
What im saying is:
Its relative simple to improve your 11 meter DX station using a horizontal high placed antenna. On low bands thats far more difficult due to the mechanical construction.

A vertical placed low will have a relative low take off angle, however it lacks gain.
But it will outperform a low placed yagi on "real" DX.
(as long as the entire "ground" system is good).

As mentioned before high horizontal antennas have additional gain due to the polarisation.
This is a additional 6dB! Bare in mind that verticals lack this amount.

Yes it is true; verticals CAN have a low take off angle.
But that will ask for a large groundsystem. Besides the massive amount of radials the ground conductivity upto at least 10 wavelengths is of vital importance! thats why verticals on ocean going boats always work and why verticals in the desert are a poor performers.
(salt sea= great conductivity)

To menion "i prefer to place my quad vertical" migth not be wise.
Below say..25 feet i will agree..But for real DX, above that height a horizontal will come out on top (real DX not your average 1000-2000 Km Sproadic Ehop).
This due to a lower toa and more gain.

Now, i have only been refering to a simple 1/4 wave vertical placed directly above ground.
as soon as we place a vertical antenna higher the toa will change aswell!
Thats not going to be always in favour!
On low bands we never see "high" placed verticals, but it is the case for about 99 procent on 11 meters!

A simple dipole at 1 wavelength high will show about 7,5dBi under a 15 degrees angle.
A simple groundplance at 1 wavelength high (4 radials) will show about 1,5dBi at that same 15 degrees angle, hence a full s-unit difference.
15 degrees is what is needed for 11 meter for a european DXer towards central africa.

You will hear people claiming great results with actually bad antennas during the summer months. This is due to sproadic E propagation which needs a relative high angle.
For sure they are poor performers when we are speaking about DX towards the otherside of the world.

Like today..108at019 / 47dx101 are the only guys working asia from northern Europa.
Both have high placed horizontal yagi's.
At the same time there is a UK guy on cluster who is happy with his beam cause he worked already 7 different countries (close range) with his low placed horizontal antenna (and its only a couple meters of the ground) He wont work DX but for sure he will set a strong signal in EU.
Thats what heigth does..simple as that.

So, my advice would be quite simple..as soon as you can put your antenna up higher than say a halve wave length and your interested in DX horizontal is the way to go without a doubt.

Just take a look at cluster.dk - the worlds biggest 11-meter radio notification system the bigguns world wide who are almost always capable of having a qso have HORIZONTAL antennas as high as 100 feet.

Anyone can claim good results from any antenna, its the expectation and reference you have which will make it valid or not.

To give an idea, i have quite an amount of guys running expeditions they all want a simple effective system.
I have had up bobtails / half squares for a half year and compared them to a simple small 3el horizontal at 8meters... we dont need to guess which one came out on top.

Kind regards,

Henry
All about antennas

 

[Captain Kilowatt]

You are right Henry about there being a difference in high bands and low bands. My point was to point out that blanket statements such as "vertical antennas are inferior to horizontal antennas" is simply not true. Call me a stickler if you want but when people make blanket statements as if they are applicable ALL the time I will jump in to point out the errors of making such blanket statements. Some people call it being educated and others call it stirring the pot a bit. I just call it as I see it. :laugh:

 

[wavrider]

Henry,

Great post and I can only echo what Captain K stated, low bands are definitely different when it comes to verticals, but so is the way the lower frequencies propagate, ( which is another topic unto itself).

The dipole has the advantage over a vertical at height, the yagi has the advantage over a dipole at the same height.

There was a fantastic article in QST magazine. either this month or last showing, comparing height of an antenna vs DX performance.

The study based the receive of DX signals and arrival angles of those signals.

Without going into great detail the study concluded that 1 and 1/2 wl for whatever frequency you are working is the optimum height for working DX from 1 to 16 degree angles.

Any height more than that adds little if any advantage for DX work. Of course local comms will benefit from higher installations.

Pardon the spelling mistakes I have misplaced my glasses.

 

[Needle Bender]

Without going into great detail the study concluded that 1 and 1/2 wl for whatever frequency you are working is the optimum height for working DX from 1 to 16 degree angles.

so are you saying at 1/2 wave high its about 16 degress and at 1 wave high its about 1 degree or were you saying it should be 1.5 waves high?

 

[W5LZ]

He's saying that about 1.5 waves above ground is a good height for low angle reception.
- 'Doc

 

[wavrider]

He's saying that about 1.5 waves above ground is a good height for low angle reception.
- 'Doc

Thanks DOC for answering the question.

For those who do not read an entire post.

I am not saying anything, I am just passing on information on an article that is in QST magazine.

 

[wavrider]

so are you saying at 1/2 wave high its about 16 degress and at 1 wave high its about 1 degree or were you saying it should be 1.5 waves high?

The degrees refer to Angle of Radiation or some call it TOA, Take off Angle.

Without typing way more than I want to the Angle of radiation is how the signal arrives to the receiving antenna or how the signal departs from the transmitting antenna.

Type of antenna and height above ground determines this TOA per say, along with a few other uncontrollable items such as buildings, structures, terrain and of course soil conductivity.

Google is your friend when it comes to information, a simple search will provide you with hours of research reading.

 

[Needle Bender]

For those who do not read an entire post.

I hope thats not a slam because I asked for clarification of your wording.

I do read entire posts, but not always everything located at a link site.

 

[Needle Bender]

The degrees refer to Angle of Radiation or some call it TOA, Take off Angle.

Without typing way more than I want to the Angle of radiation is how the signal arrives to the receiving antenna or how the signal departs from the transmitting antenna.

Type of antenna and height above ground determines this TOA per say, along with a few other uncontrollable items such as buildings, structures, terrain and of course soil conductivity.

Google is your friend when it comes to information, a simple search will provide you with hours of research reading.

OK, I do understand toa but when you stated "1 and 1/2" instead of 1.5 or 1 1/2 and then stated 1 degree up to 16 degrees I wondered if those were two separate options and related 2 different heights to 2 different angles. No harm, no foul. :laugh:

 

[wavrider]

OK, I do understand toa but when you stated "1 and 1/2" instead of 1.5 or 1 1/2 and then stated 1 degree up to 16 degrees I wondered if those were two separate options and related 2 different heights to 2 different angles. No harm, no foul. :laugh:

None taken or meant.