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.
>>
>>
>>
>>
>>
>> _______________________________________________
>>
>>
>>
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>>
>
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>
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