Getting things together here to get the antenna/rotor, switchbox up on
the tower and plan for the half square for the lower bands. I've had
this in a file and wanted to share it. Good information about takeoff
angles and height above ground:
http://radio.n0gw.net/radio12.pdf
Mike, k5wmg
On Thu, Dec 1, 2011 at 12:43 PM, Gene Fuller <w2lu@rochester.rr.com> wrote:
> 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
>>>> http://lists.contesting.com/mailman/listinfo/towertalk
>>>> or, via email, send a message with subject or body 'help' to
>>>> towertalk-request@contesting.com
>>>>
>>>> You can reach the person managing the list at
>>>> towertalk-owner@contesting.com
>>>>
>>>> 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
>
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
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