Hi Bill;
If your're using 1/4w 75 ohm lines to the towers from your coupler, try
three top-loading wires, each at 20 feet initially on each tower, to
retain your 75 ohm lines.
If this is not satisfactory, then the "L" configuration, with all wires
pointed towards the center, will work well. However, Inverted L's
exhibit a lower impedence vs series fed 1/4w verticals, and you will have
to install fifty (50) ohm 1/4 w lines. K1ZM experienced this with his
160M 4-Square in New England several years ago, and is described in his
book, DXing on the Edge, published by ARRL.
Good luck, and I guess we will have to wait a winter to see what option
is best suited for your QTH!
73,
Jim Miller, K4SQR
http://www.comteksystems.com
4-Square Experts, Stack Yagi
& Remote Antenna Switching Systems
On Wed, 13 Jun 2001 11:59:28 -0700 (PDT) BILL STRAW <wb0o@yahoo.com>
writes:
> 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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Jim Miller, K4SQR
http://www.comteksystems.com
4-Square Experts, Stack Yagi
& Remote Antenna Switching Systems
List Sponsor: Are you thinking about installing a tower this summer? Call us
for information on our fabulous Trylon Titan self-supporting towers - up to
96-feet for less than $2000! at 888-833-3104 <A
HREF="http://www.ChampionRadio.com";>
www.ChampionRadio.com</A>
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