-
You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
¿ is height really might?
- Thread starter Wire Dawg
- Start date
I was able to contact the old stations again, and they report no big difference in my signal strenght. The additional height has allow some new dx contacts, but placing the antenna above the one wavelenght mark has not given the results I expected (so far).
Too many people put stock in this magical height thing of one wavelength. It's as if they think something grand will happen the moment they get their antenna up a full wavelength. It doesn't work that way. Everything is a gradual change as height is improved and there is no magicl and mystical height when things will suddenly start to work better. One thing that 99.9% of the people that talk about this height thing either miss or have no idea about in the first place is that the height above ground is referencing RF ground and not the plain old dirt that you walk on. Depending on your soil type RF ground can be several feet ( up to 8 or more in some areas) below the grass level so that can throw the one wavelength above ground thing off a lot......well a full quarter wavelength on 11m in some cases.
The truth is that the angle of radiation does get lower as the antenna gets higher but it is a gradual thing and nothing happens suddenly. My advise to anyone is to get the antenna up as high as you can and try it. If you don't like the results buy more tower and go higher. You can never go wrong with going higher.
The truth is that the angle of radiation does get lower as the antenna gets higher but it is a gradual thing and nothing happens suddenly. My advise to anyone is to get the antenna up as high as you can and try it. If you don't like the results buy more tower and go higher. You can never go wrong with going higher.
Should've sought advise in this forum, as I did for buying the radio. Most articles that I read regarding antenna height, TOA, gain, polarization, etc supported an ideal height of 1 to 1.5 WL of the primary hf frequency. Went thru hell & back to obtain a city permit and pass inspection (not to mention expenses of the tower itself). Truly an expensive lesson in the pursuit of DX nirvana. The sense of accomplishment is nice, but still dissapointed at finding that reaching the 1 wl antenna height is no panacea.
I think that 1or 1.5 wavelength figure is really a guide from where you can begin to see the true potential of your antenna system. Beyond that there is little to be gained and only in a small percentage of the time.
Dx is a funny mistress.
So many different means of propagation to be considered.
E layers, F layers and lets not forget back scatter and the mysterious SKYWAVE.
I have had a yagi 8 feet off the ground doing maintenance on it. finish the work turn the rig on to see how it is and hear Japan on 15 meters????
Height is might?? Yes it is.
There is no magical number in height above ground. Many ops, engineers and such have stated 1 to 1.5WL is optimal for long distance DX.
To bad they did not ask mother natures opinion on optimal height, not that she would have replied to the question as she is a finicky old hag to say the least.
The height you have your antenna at is a good height for all around comms, local and DX. If you can hear then you should be able to work them per say.
So many different means of propagation to be considered.
E layers, F layers and lets not forget back scatter and the mysterious SKYWAVE.
I have had a yagi 8 feet off the ground doing maintenance on it. finish the work turn the rig on to see how it is and hear Japan on 15 meters????
Height is might?? Yes it is.
There is no magical number in height above ground. Many ops, engineers and such have stated 1 to 1.5WL is optimal for long distance DX.
To bad they did not ask mother natures opinion on optimal height, not that she would have replied to the question as she is a finicky old hag to say the least.
The height you have your antenna at is a good height for all around comms, local and DX. If you can hear then you should be able to work them per say.
Last edited:
Law of diminishing returns
When does the law of diminishing returns take effect? I figured anything over 100 ft for 11m is overkill...just my made up opinion with no facts to prove it! I've Also heard one you go above the 2nd wavelength, you will get a increase In white noise. Any truth to this?? Oh and btw this
Is in reference to ground wave, not skip.
When does the law of diminishing returns take effect? I figured anything over 100 ft for 11m is overkill...just my made up opinion with no facts to prove it! I've Also heard one you go above the 2nd wavelength, you will get a increase In white noise. Any truth to this?? Oh and btw this
Is in reference to ground wave, not skip.
"When does the law of diminishing returns take effect?"
I goes into effect when you think it does.
"I figured anything over 100 ft for 11m is overkill...just my made up opinion with no facts to prove it!"
That's as good an opinion as any. I have to agree with you though, but not for the same reasons. I CAn't put up a 100 foot tower.
"I've Also heard one you go above the 2nd wavelength, you will get a increase In white noise. Any truth to this??"
I have no idea, but even so, I think the increase in the other types of received signals would out weigh it.
"Oh and btw this
Is in reference to ground wave, not skip."
And how would it make any difference if that increase in 'white noise' didn't interfere with either local or 'skip'? Swapping polarity would take care of most noises of that sort. Of course it would also affect what you heard, increase in some signals and a decrease in others.
Basically, it's a matter of quitting when it isn't worth it anymore. How do you decide that? That's sort of up to you, isn't it? I can honestly say that I've never heard of anyone lowering a tower because it was too high for good reception.
- 'Doc
I goes into effect when you think it does.
"I figured anything over 100 ft for 11m is overkill...just my made up opinion with no facts to prove it!"
That's as good an opinion as any. I have to agree with you though, but not for the same reasons. I CAn't put up a 100 foot tower.
"I've Also heard one you go above the 2nd wavelength, you will get a increase In white noise. Any truth to this??"
I have no idea, but even so, I think the increase in the other types of received signals would out weigh it.
"Oh and btw this
Is in reference to ground wave, not skip."
And how would it make any difference if that increase in 'white noise' didn't interfere with either local or 'skip'? Swapping polarity would take care of most noises of that sort. Of course it would also affect what you heard, increase in some signals and a decrease in others.
Basically, it's a matter of quitting when it isn't worth it anymore. How do you decide that? That's sort of up to you, isn't it? I can honestly say that I've never heard of anyone lowering a tower because it was too high for good reception.
- 'Doc
Real "ground wave" doesn't exist much above above 3 MHz, and certainly not at 27 MHz.
perhaps what you are refering to is really "direct wave".
True ground wave requires vertical antennas at both ends, because the path only supports vertically polarized radiation.
Most local work on the higher bands (and certainly for CB) is actually direct radiation, higher antennas give longer range.
Agreed. Probably 99% of the people call communications that does not take place via skip ground wave simply because sky wave is via skip so ground wave must be without skip.
Height = Might, sometimes, I guess it depends what that height means, real long haul DX, yeas height every time, however that isn't always the case, a study of arrival angles will give you an indication of the take off angle required to achieve a particular goal, and here one size does not fit all, that's why high performance and contest stations invest considerable sums in stacked arrays, that means putting their antennas at different heights so they can maximise their signal, both received and transmitted, in a particular area or part of the World.
If you have a telescoping tower then there's no reason why you can't adjust the height to suit your particular goals
If you have a telescoping tower then there's no reason why you can't adjust the height to suit your particular goals
B
BOOTY MONSTER
Guest
FWIU the biggest thing is if you can get the lowest part of the antenna above any nearby roof tops . trees don't effect signals as much as buildings can , but if it's easily affordable enough to get above them .... go for it .