Bill,
Sorry for the slight delay re your question, I have been working on my top
loaded 80m 4SQ. In my array I played around on the PC with using 2
horizontal loading wires held up by double pulley blocks on each adjacent
vertical. This keeps the base Z as high as possible and can easily be
tested. Just remove all your top whips and replace on one tower only two top
loading wires held up by the tower on each of its sides. Get it resonant
where you want it and then repeat it around the Square. I have used SS wire
with crimped SS eyes on each wire for the loading. They are unlikely to
break and from experience are the best material for durable top loading.
If you heard my 80m signal last winter that was just one top loaded vertical
40ft with SS loading and a big ground system.
73 Clive GM3POI
----- Original Message -----
From: "BILL STRAW" <wb0o@yahoo.com>
To: <towertalk@contesting.com>
Sent: Wednesday, June 13, 2001 6:59 PM
Subject: [TowerTalk] Vertical top-loading questions
> A quick question:
>
> I have an elevated 80M 4-square made of Rohn 25. There
> is 15' of tower, then an insulator, then 50' of tower,
> then a 20' whip made of aluminum tubing. Every winter
> one or more of the whips break off (even using triple
> wall tubing). This year 3 broke off. I have to do
> something:
>
> 1) Extend each vertical with 1 or 2 more sections of
> tower. This costs $. I have the tower, but the
> Phillstran, and Grips X 4 towers adds up quick.
> 2) Take the whips off and top load each tower with a
> piece of wire strung to the top of another tower.
> Thus I would have 4 inverted-L's, but the top
> horizontal portion would be exactly horizontal.
>
> Would #2 alter the gain or pattern much? I think it
> would decrease the bandwith, but this antenna is used
> mainly on CW.
>
> Thanks for any opinions.
> Bill, WB0O in North Dakota
>
>
>
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