Optimum height for a tower is a classic case of "it all depends". What are
your interests?, What's the geography like at your QTH?, Are there
obstructions?, Are there zoning restrictions? , What's the budget?, Will
maintenance be a consideration? etc. If you're a dx'er - what bands?
Although, for horizontal polarization, radiation angle is a function of
height in wavelengths, optimum radiation angle is also a function of
frequency, path, band conditions, even receive antenna height, etc.. When
all of the factors are put on the scales, 70 feet very often turns out to be
a good balance point, but higher and lower certainly can be optimum for
particular interests. There's no "silver bullet".
Gene / W2LU
----- Original Message -----
From: "Joe Subich, W4TV" <lists@subich.com>
To: "Drax Felton" <draxfelton@gmail.com>; "[TowerTalk]"
<towertalk@contesting.com>
Sent: Thursday, December 01, 2011 12:08 PM
Subject: Re: [TowerTalk] Cost effectivel Tower height
>
> > Isn't the a half wave high tower the general rule of thumb for a
> > decent dx angle?
>
> No, 1/2 wave is where a horizontally polarized antenna shows its
> first null directly overhead.
>
> > After 60ft (1/2 wave on 20m)
>
> 60 ft is 0.86 wave on 20 meters (14 MHz) - one wavelength is 70 feet.
>
> If I had to choose a single tower height *over flat ground* it would be
> 70 feet. That represents 1/2 wave on 40 meters - a point that a dipole
> or two element Yagi has some decent (but not world beating) performance
> - and a useful height for an 80 meter inverted V or a place to hang
> inverted L antennas for 160 and 80. In addition, 70 feet in 1 1/5 wave
> on 15 meters (perhaps the most useful overall height for DX) and 2
> waves on 10 (high but not too high except for short skip).
>
> > After 60ft (1/2 wave on 20m) you need more guys with Rohn 25
>
> Two levels of guying is acceptable with Rohn 25 up to 70 feet. Rohn 45
> will go to 90 feet with two levels of guying.
>
> 73,
>
> ... Joe, W4TV
>
>
> On 12/1/2011 11:53 AM, Drax Felton wrote:
>> Isn't the a half wave high tower the general rule of thumb for a decent
>> dx angle?
>>
>> After 60ft (1/2 wave on 20m) you need more guys with Rohn 25 and the
>> work difficulty starts increasing rapidly.
>>
>> Sent from my iPhone
>>
>> On Dec 1, 2011, at 12:31 AM, towertalk-request@contesting.com wrote:
>>
>>> Send TowerTalk mailing list submissions to
>>> towertalk@contesting.com
>>>
>>> To subscribe or unsubscribe via the World Wide Web, visit
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>>> or, via email, send a message with subject or body 'help' to
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>>> When replying, please edit your Subject line so it is more specific
>>> than "Re: Contents of TowerTalk digest..."
>>>
>>>
>>> Today's Topics:
>>>
>>> 1. Determine cost-effective tower height (Andreas Hofmann)
>>> 2. Re: Determine cost-effective tower height (Jim Lux)
>>> 3. Re: Determine cost-effective tower height (Dick Dievendorff)
>>> 4. Re: Determine cost-effective tower height (Gene Fuller)
>>> 5. Re: Determine cost-effective tower height (Dick Dievendorff)
>>> 6. FW: Determine cost-effective tower height (km5vi)
>>> 7. Re: Determine cost-effective tower height (Jim Lux)
>>> 8. top loaded vertical radial length (LY2KZ)
>>>
>>>
>>> ----------------------------------------------------------------------
>>>
>>> Message: 1
>>> Date: Thu, 1 Dec 2011 00:47:46 +0000
>>> From: Andreas Hofmann<Andreas.Hofmann@microsoft.com>
>>> Subject: [TowerTalk] Determine cost-effective tower height
>>> To: "towertalk@contesting.com"<towertalk@contesting.com>
>>> Message-ID:
>>>
>>> <A9B46A478518064C8E335B938C8768840EBE9F66@TK5EX14MBXC288.redmond.corp.microsoft.com>
>>>
>>> Content-Type: text/plain; charset="us-ascii"
>>>
>>> Hi,
>>>
>>> I have decided I need a tower to get better antennas up in the air.
>>> Thinking about the SteppIR DB 18, 40m 2 el, 20 and up 3el. Now, my
>>> property slopes pretty much in every direction by 5 degrees. I need to
>>> determine a proper tower height without breaking the bank.
>>>
>>> I was told I should run a computer program to figure a good height of
>>> the yagi for my most important directions/DX locations. In fact a
>>> friend of mine did the same (on a similarly sloping property) and he
>>> found out that a 55 foot tower would be similar to a 120 foot tower on a
>>> flat ground. Hence he put up a 55 foot crank up mast and it is
>>> rocking. He forgot the program he used.
>>>
>>> So, what tool can I use to find the optimal (not maximal) height of a
>>> tower that would work well here?
>>> Also, the tower would be setting on the side of the house with a metal
>>> roof (roof about 15 feet high), not sure if this would matter...
>>>
>>> Thanks
>>> Andreas
>>> KU7T
>>>
>>>
>>>
>>>
>>> ------------------------------
>>>
>>> Message: 2
>>> Date: Wed, 30 Nov 2011 16:59:54 -0800
>>> From: Jim Lux<jimlux@earthlink.net>
>>> Subject: Re: [TowerTalk] Determine cost-effective tower height
>>> To: towertalk@contesting.com
>>> Message-ID:<4ED6D18A.10405@earthlink.net>
>>> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>>>
>>> On 11/30/11 4:47 PM, Andreas Hofmann wrote:
>>>> Hi,
>>>>
>>>> I have decided I need a tower to get better antennas up in the air.
>>>> Thinking about the SteppIR DB 18, 40m 2 el, 20 and up 3el. Now, my
>>>> property slopes pretty much in every direction by 5 degrees. I need to
>>>> determine a proper tower height without breaking the bank.
>>>>
>>>> I was told I should run a computer program to figure a good height of
>>>> the yagi for my most important directions/DX locations. In fact a
>>>> friend of mine did the same (on a similarly sloping property) and he
>>>> found out that a 55 foot tower would be similar to a 120 foot tower on
>>>> a flat ground. Hence he put up a 55 foot crank up mast and it is
>>>> rocking. He forgot the program he used.
>>>>
>>>> So, what tool can I use to find the optimal (not maximal) height of a
>>>> tower that would work well here?
>>>> Also, the tower would be setting on the side of the house with a metal
>>>> roof (roof about 15 feet high), not sure if this would matter...
>>>>
>>>> Thanks
>>>> Andreas
>>>> KU7T
>>>>
>>>
>>> HFTA by Ward Silver which comes with the ARRL Antenna Book is what you
>>> want. You enter in the surrounding terrain (or extract it from DEM
>>> files, etc.) and it calculates the pattern.
>>>
>>> Only works for horizontally polarized antennas, by the way.
>>>
>>>
>>> ------------------------------
>>>
>>> Message: 3
>>> Date: Wed, 30 Nov 2011 17:25:50 -0800
>>> From: "Dick Dievendorff"<dieven@comcast.net>
>>> Subject: Re: [TowerTalk] Determine cost-effective tower height
>>> To: "'Jim Lux'"<jimlux@earthlink.net>,<towertalk@contesting.com>
>>> Message-ID:<001b01ccafc8$29967cf0$7cc376d0$@comcast.net>
>>> Content-Type: text/plain; charset="US-ASCII"
>>>
>>> I think HFTA is by Dean Straw, N6BV. In any case, it's the program you
>>> want
>>> for this. Ward edited the new Antenna Book, and included Dean's
>>> programs.
>>>
>>> Dick, K6KR
>>>
>>> -----Original Message-----
>>> From: towertalk-bounces@contesting.com
>>> [mailto:towertalk-bounces@contesting.com] On Behalf Of Jim Lux
>>> Sent: Wednesday, November 30, 2011 5:00 PM
>>> To: towertalk@contesting.com
>>> Subject: Re: [TowerTalk] Determine cost-effective tower height
>>>
>>> On 11/30/11 4:47 PM, Andreas Hofmann wrote:
>>>> Hi,
>>>>
>>>> I have decided I need a tower to get better antennas up in the air.
>>> Thinking about the SteppIR DB 18, 40m 2 el, 20 and up 3el. Now, my
>>> property
>>> slopes pretty much in every direction by 5 degrees. I need to determine
>>> a
>>> proper tower height without breaking the bank.
>>>>
>>>> I was told I should run a computer program to figure a good height of
>>>> the
>>> yagi for my most important directions/DX locations. In fact a friend of
>>> mine did the same (on a similarly sloping property) and he found out
>>> that a
>>> 55 foot tower would be similar to a 120 foot tower on a flat ground.
>>> Hence
>>> he put up a 55 foot crank up mast and it is rocking. He forgot the
>>> program
>>> he used.
>>>>
>>>> So, what tool can I use to find the optimal (not maximal) height of a
>>> tower that would work well here?
>>>> Also, the tower would be setting on the side of the house with a metal
>>> roof (roof about 15 feet high), not sure if this would matter...
>>>>
>>>> Thanks
>>>> Andreas
>>>> KU7T
>>>>
>>>
>>> HFTA by Ward Silver which comes with the ARRL Antenna Book is what you
>>> want.
>>> You enter in the surrounding terrain (or extract it from DEM files,
>>> etc.)
>>> and it calculates the pattern.
>>>
>>> Only works for horizontally polarized antennas, by the way.
>>> _______________________________________________
>>>
>>>
>>>
>>> _______________________________________________
>>> TowerTalk mailing list
>>> TowerTalk@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/towertalk
>>>
>>>
>>>
>>> ------------------------------
>>>
>>> Message: 4
>>> Date: Wed, 30 Nov 2011 21:09:30 -0500
>>> From: "Gene Fuller"<w2lu@rochester.rr.com>
>>> Subject: Re: [TowerTalk] Determine cost-effective tower height
>>> To: "Dick Dievendorff"<dieven@comcast.net>, "'Jim Lux'"
>>> <jimlux@earthlink.net>,<towertalk@contesting.com>
>>> Message-ID:<E2520ACDBCEE43858C2FEB22186E5240@FamilyRoom>
>>> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
>>> reply-type=original
>>>
>>> Agreed, HFTA is the way to go. ARRL Antenna Handbook ed 21 includes
>>> the
>>> software and instrustrutions you will need. A little hand held GPS will
>>> give
>>> you your tower location, and a fair bit of determination for the novice,
>>> will give you a great picture of what you have to work with.
>>> Gene / W2LU
>>>
>>>
>>>
>>>
>>> ----- Original Message -----
>>> From: "Dick Dievendorff"<dieven@comcast.net>
>>> To: "'Jim Lux'"<jimlux@earthlink.net>;<towertalk@contesting.com>
>>> Sent: Wednesday, November 30, 2011 8:25 PM
>>> Subject: Re: [TowerTalk] Determine cost-effective tower height
>>>
>>>
>>>> I think HFTA is by Dean Straw, N6BV. In any case, it's the program you
>>>> want
>>>> for this. Ward edited the new Antenna Book, and included Dean's
>>>> programs.
>>>>
>>>> Dick, K6KR
>>>>
>>>> -----Original Message-----
>>>> From: towertalk-bounces@contesting.com
>>>> [mailto:towertalk-bounces@contesting.com] On Behalf Of Jim Lux
>>>> Sent: Wednesday, November 30, 2011 5:00 PM
>>>> To: towertalk@contesting.com
>>>> Subject: Re: [TowerTalk] Determine cost-effective tower height
>>>>
>>>> On 11/30/11 4:47 PM, Andreas Hofmann wrote:
>>>>> Hi,
>>>>>
>>>>> I have decided I need a tower to get better antennas up in the air.
>>>> Thinking about the SteppIR DB 18, 40m 2 el, 20 and up 3el. Now, my
>>>> property
>>>> slopes pretty much in every direction by 5 degrees. I need to
>>>> determine a
>>>> proper tower height without breaking the bank.
>>>>>
>>>>> I was told I should run a computer program to figure a good height of
>>>>> the
>>>> yagi for my most important directions/DX locations. In fact a friend
>>>> of
>>>> mine did the same (on a similarly sloping property) and he found out
>>>> that
>>>> a
>>>> 55 foot tower would be similar to a 120 foot tower on a flat ground.
>>>> Hence
>>>> he put up a 55 foot crank up mast and it is rocking. He forgot the
>>>> program
>>>> he used.
>>>>>
>>>>> So, what tool can I use to find the optimal (not maximal) height of a
>>>> tower that would work well here?
>>>>> Also, the tower would be setting on the side of the house with a metal
>>>> roof (roof about 15 feet high), not sure if this would matter...
>>>>>
>>>>> Thanks
>>>>> Andreas
>>>>> KU7T
>>>>>
>>>>
>>>> HFTA by Ward Silver which comes with the ARRL Antenna Book is what you
>>>> want.
>>>> You enter in the surrounding terrain (or extract it from DEM files,
>>>> etc.)
>>>> and it calculates the pattern.
>>>>
>>>> Only works for horizontally polarized antennas, by the way.
>>>> _______________________________________________
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> TowerTalk mailing list
>>>> TowerTalk@contesting.com
>>>> http://lists.contesting.com/mailman/listinfo/towertalk
>>>>
>>>> _______________________________________________
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> TowerTalk mailing list
>>>> TowerTalk@contesting.com
>>>> http://lists.contesting.com/mailman/listinfo/towertalk
>>>
>>>
>>>
>>> ------------------------------
>>>
>>> Message: 5
>>> Date: Wed, 30 Nov 2011 18:19:50 -0800
>>> From: "Dick Dievendorff"<dieven@comcast.net>
>>> Subject: Re: [TowerTalk] Determine cost-effective tower height
>>> To: "'Gene Fuller'"<w2lu@rochester.rr.com>, "'Jim Lux'"
>>> <jimlux@earthlink.net>,<towertalk@contesting.com>
>>> Message-ID:<001801ccafcf$b4a4c4d0$1dee4e70$@comcast.net>
>>> Content-Type: text/plain; charset="us-ascii"
>>>
>>> Google Earth is another (free) tool that you can use to determine the
>>> latitude and longitude of your specific antenna location.
>>>
>>> Dick
>>>
>>>
>>> -----Original Message-----
>>> From: Gene Fuller [mailto:w2lu@rochester.rr.com]
>>> Sent: Wednesday, November 30, 2011 6:10 PM
>>> To: Dick Dievendorff; 'Jim Lux'; towertalk@contesting.com
>>> Subject: Re: [TowerTalk] Determine cost-effective tower height
>>>
>>> Agreed, HFTA is the way to go. ARRL Antenna Handbook ed 21 includes
>>> the
>>> software and instrustrutions you will need. A little hand held GPS will
>>> give
>>> you your tower location, and a fair bit of determination for the novice,
>>> will give you a great picture of what you have to work with.
>>> Gene / W2LU
>>>
>>>
>>>
>>>
>>> ----- Original Message -----
>>> From: "Dick Dievendorff"<dieven@comcast.net>
>>> To: "'Jim Lux'"<jimlux@earthlink.net>;<towertalk@contesting.com>
>>> Sent: Wednesday, November 30, 2011 8:25 PM
>>> Subject: Re: [TowerTalk] Determine cost-effective tower height
>>>
>>>
>>>> I think HFTA is by Dean Straw, N6BV. In any case, it's the program you
>>>> want
>>>> for this. Ward edited the new Antenna Book, and included Dean's
>>>> programs.
>>>>
>>>> Dick, K6KR
>>>>
>>>> -----Original Message-----
>>>> From: towertalk-bounces@contesting.com
>>>> [mailto:towertalk-bounces@contesting.com] On Behalf Of Jim Lux
>>>> Sent: Wednesday, November 30, 2011 5:00 PM
>>>> To: towertalk@contesting.com
>>>> Subject: Re: [TowerTalk] Determine cost-effective tower height
>>>>
>>>> On 11/30/11 4:47 PM, Andreas Hofmann wrote:
>>>>> Hi,
>>>>>
>>>>> I have decided I need a tower to get better antennas up in the air.
>>>> Thinking about the SteppIR DB 18, 40m 2 el, 20 and up 3el. Now, my
>>>> property
>>>> slopes pretty much in every direction by 5 degrees. I need to
>>>> determine a
>>>> proper tower height without breaking the bank.
>>>>>
>>>>> I was told I should run a computer program to figure a good height of
>>>>> the
>>>> yagi for my most important directions/DX locations. In fact a friend
>>>> of
>>>> mine did the same (on a similarly sloping property) and he found out
>>>> that
>>>> a
>>>> 55 foot tower would be similar to a 120 foot tower on a flat ground.
>>>> Hence
>>>> he put up a 55 foot crank up mast and it is rocking. He forgot the
>>>> program
>>>> he used.
>>>>>
>>>>> So, what tool can I use to find the optimal (not maximal) height of a
>>>> tower that would work well here?
>>>>> Also, the tower would be setting on the side of the house with a metal
>>>> roof (roof about 15 feet high), not sure if this would matter...
>>>>>
>>>>> Thanks
>>>>> Andreas
>>>>> KU7T
>>>>>
>>>>
>>>> HFTA by Ward Silver which comes with the ARRL Antenna Book is what you
>>>> want.
>>>> You enter in the surrounding terrain (or extract it from DEM files,
>>>> etc.)
>>>> and it calculates the pattern.
>>>>
>>>> Only works for horizontally polarized antennas, by the way.
>>>> _______________________________________________
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> TowerTalk mailing list
>>>> TowerTalk@contesting.com
>>>> http://lists.contesting.com/mailman/listinfo/towertalk
>>>>
>>>> _______________________________________________
>>>>
>>>>
>>>>
>>>> ___________
>>>
>> _______________________________________________
>>
>>
>>
>> _______________________________________________
>> TowerTalk mailing list
>> TowerTalk@contesting.com
>> http://lists.contesting.com/mailman/listinfo/towertalk
>>
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
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