Antenna height questions

[Christopher17]

Putting up 5/8 Ground Plane , Don't have it yet, (still playing with the home brew 5/8) I like the zero five but probably going with the hy-gain due to price, got enough rohm tower sections to get feed point to 30 or so feet, my elevation is right at 500 feet and the terrain is Sandy soil with dense woods, my question is "how critical is mounting height?" Should I get the feed point to the 36 foot mark? Should the antenna be in the middle of the second wave? Is it best to have the top of the antenna at the top of the wave, or the feed point at the bottom of the wave, I assumed the antenna should be centered in or the middle of second wave or is this just more misinformation and myths about wavelength and mounting height, I always hear height is might, if I had it say centered at 36 feet (between the 2 waves) would it be worse than say at 14 feet off the ground?

 

[sp5it]

Not much difference, but higher-better.

Mike

 

[w9cll]

Higher is better but at some point you hit the wall of demishing returns. It will cost more to go higher and very little improvement in signal. I would say the base of the antenna at 40' is a good place to be.

 

[M0GVZ]

The difference between 30ft and 40ft is so little as to not be worth spending any money doing it.

 

[357magnum]

All I know is my A-99 is on a 30' push pole , fully extended , my guess is 48' to the tip . I have Np's , but then again I checked my elevation , up on a hill 679' OSL . It just works for me ! Stay Healthy & Safe ! 73 & God Bless , Leo Btw Chris , how are you feeling ?

 

[groundwire]

I/2 wavelength above ground at the feed point will give you a relatively low radiation angle, good for dx. 1/4 wavelength will keep the radiation angle fairly high, good for local talk with some. Low angle properties for dx. Basically 1/2 to 5/8 wavelength above ground. Is the sweet spot. It can get pretty technical as far as height versus lobes

 

[2NC995]

The little bit of reading and studying I have done seems to indicate that it’s also highly dependent on the type of ground under the antenna.

Salt plains vs rocky mountain side...in other words.

I don’t have much to worry about...my feed point is at 6 feet, and I can’t afford bigger tires or a lift kit.

 

[Road Squawker]

The little bit of reading and studying I have done seems to indicate that it’s also highly dependent on the type of ground under the antenna... edit....

Not to confuse the ideas, but, most "ground" here in the U.S., is actually 3 to 6 feet below the earths surface.

 

[2NC995]

Not to confuse the ideas, but, most "ground" here in the U.S., is actually 3 to 6 feet below the earths surface.

Maybe a tad of idea confusing, but a welcome response nonetheless.

 

[W4KVW]

The difference between 30ft and 40ft is so little as to not be worth spending any money doing it.

The difference is being under one wave length & being just above one wave length so it could be a Big difference.

SIX-SHOOTER

 

[binrat]

The little bit of reading and studying I have done seems to indicate that it’s also highly dependent on the type of ground under the antenna

I have found this to be true. Sandy soil with vegetation, higher the better. Primarily rock, low works as good.

 

[kopcicle]

Generally above ground works best

 

[Dmans]

If Bobby (undertaker) didn't "like" this comment, I would have been extremely disappointed.

Love ya' Man!

73
David

 

[Shadetree Mechanic]

Generally above ground works best

It depends on who you are trying to talk to.
https://en.m.wikipedia.org/wiki/Through-the-earth_mine_communications

 

[Christopher17]

The difference is being under one wave length & being just above one wave length so it could be a Big difference.

SIX-SHOOTER

that's what I was thinking