I know K4SSU has turn down the fibeglass and make insulators for Rohn 25.
Ron K4WZ
----- Original Message -----
From: "Mark Robinson" <markrob@mindspring.com>
To: "jeremy-ca" <km1h@jeremy.mv.com>; "James Bloomfield"
<rn23crna@windstream.net>; <towertalk@contesting.com>
Sent: Tuesday, June 19, 2007 5:47 PM
Subject: Re: [TowerTalk] Tower Insulators
>A friend of mine made Rohn 25 insulators for his 80m 4 square by turning
> down fiberglass rods
>
> Mark N1UK G3ZZM
>
> ----- Original Message -----
> From: "jeremy-ca" <km1h@jeremy.mv.com>
> To: "James Bloomfield" <rn23crna@windstream.net>;
> <towertalk@contesting.com>
> Sent: Tuesday, 19 June, 2007 5:42 PM
> Subject: Re: [TowerTalk] Tower Insulators
>
>
>> The ones mentioned are $400 and $1145! Ouch!
>>
>> Consider feeding the tower as a folded unipole, all you need is some
>> copper
>> wire. Ham literature shows a single drop wire; commercial AMers use 3 to
>> 6
>> and report improved bandwidth when the electrical length is 110-115
>> degrees..
>>
>> Carl
>> KM1H
>>
>>
>>
>> ----- Original Message -----
>> From: "James Bloomfield" <rn23crna@windstream.net>
>> To: <towertalk@contesting.com>
>> Sent: Tuesday, June 19, 2007 2:52 PM
>> Subject: [TowerTalk] Tower Insulators
>>
>>
>>>
>>>
>>> I plan to install a 90 ft. vertical Rohn 25 that is fed with two 'L'
>>> networks for 160 and 80 meters.
>>>
>>>
>>>
>>> This is described in Low-Band DXing by John Devoldere ON4UN.
>>>
>>>
>>>
>>> I think I can do everything necessary except I have not been able to
>>> find insulators for the base of the tower. There was one commercial
>>> source
>>> but they wanted $300.00.
>>>
>>>
>>>
>>> This is a 'budget' project. The towers were acquired by taking down
>>> "TV" towers that were no longer in use. The Coax is commercial hardline
>>> purchased for $30.00 (260 ft!)
>>>
>>>
>>>
>>> The only 'plan' that I have is to build 6 metal disc welded to rods
>>> that
>>> fit inside the tower legs. They would be insulated with Lexan and
>>> bolted
>>> together in such a way that the bolts would also be insulated. I have
>>> some
>>> 1/2 inch lexan - from a flee market.
>>>
>>>
>>>
>>> I am aware that Rohn made insulators for the tower legs but they are
>>> no
>>> longer available.
>>>
>>>
>>>
>>> Ideas and opinions are needed and welcome.
>>>
>>>
>>>
>>> KV4FE
>>>
>>> Jim Bloomfield
>>>
>>> On the Suwannee River
>>>
>>> Fl.
>>>
>>>
>>>
>>>
>>>
>>> _______________________________________________
>>>
>>>
>>>
>>> _______________________________________________
>>> TowerTalk mailing list
>>> TowerTalk@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/towertalk
>>>
>>
>> _______________________________________________
>>
>>
>>
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>
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>
>
>
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