Yes Collin, that sounds right to me, although most of us just put'em up as
high as we can, and that's all we can do. I think you're right though, a
half wave is the minimum if you want your dipole to behave like a dipole.
-----Original Message-----
From: Colin McDonald
Sent: Sunday, July 06, 2014 1:14 PM
To: [log in to unmask]
Subject: Re: half wave length height equation
From what I recall, a balanced dipole style antenna should be 1 half wave
above ground to achieve the best results. Higher will make the antenna work
better as well.
I think with the G5RV, they recommend it be at least 10 meters, or half wave
on 20 meters above ground to work well on those bands. If you want a good
40 or 80 meter antenna, they have to go as high as you can get them or it
will act more like an NVIS antenna.
The thing is, most people who can string a wire up at 120 feet can usually
put up something more substantial than a g5rv lol.
The half wave above ground for a dipole has to do with how the antenna works
against ground, and it's angle of radiation and lobe patern etc...at least I
think so from 10 years ago when I studied for the license lol.
73
Colin, V A6BKX
--------------------------------------------------
From: "Lou Kolb" <[log in to unmask]>
Sent: Sunday, July 06, 2014 11:53 AM
To: <[log in to unmask]>
Subject: Re: half wave length height equation
> Guys,
>
> Unless I misunderstand, I believe patrick is looking for a formula for
> optimum height above ground, not length of antenna. Unfortunately, I don't
> have the answer either. Hopefully, someone else on here will.
> Lou Kolb
> Voice-over Artist:
> Radio/TV Ads, Video narrations
> Messages On-hold:
> www.loukolb.com
> ----- Original Message -----
> From: "Jim Shaffer" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Sunday, July 06, 2014 12:20 PM
> Subject: Re: half wave length height equation
>
>
>> To get the half wave length in feet, use 468/f, where f is in MHZ.
>>
>> The 300 / f / 2 equasion gives you the half wave length in meters.
>> --
>> Jim, KE5AL
>>
>> -----Original Message-----
>> From: Patrick Johnson
>> Sent: Sunday, July 06, 2014 8:54 AM
>> To: [log in to unmask]
>> Subject: half wave length height equation
>>
>> Group,
>>
>> I remember QST had an article on how to figure the optim height for a
>> horizontal antenna, and of course I can't find it at the moment. I am
>> trying to remember the equation to figure out half wave lengths.
>>
>> Does the following sound correct?
>>
>> (H (in feet)=300/f (in MHz))/2 ?
>>
>> With the recent conversation about verticals I want tofigure out the
>> optim height to hang a pair of G5RVs.
>>
>> 73s,
>>
>> patrick
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