[TenTec] Re: Ten Tec antenna tuners (ladderline lore)

Carter Grabarczyk k8vt@ameritech.net
Sun, 02 Apr 2000 09:51:26 -0400

Paul Christensen wrote:
> Well, since posting my inquiry yesterday, I received a lot of expanations
> for the practice of twisting balanced transmission line.  Here is a summary
> of the majority of replies:
> 1) Twisting the lines reduces motion due to wind loading effects.

Wouldn't twisting make the wind loading WORSE? Take a hundred foot run
of ladder line to your antenna without any twists. Now use a twisted
ladder line to go to the same antenna the same 100 feet away. Because of
the twist, you will actually have used some amount of cable GREATER than
100 feet. Now, instead of 100 feet of cable in the air, you will have
101 or 105 feet or whatever in the air (depending on how tight the
twist). In any event, you will have MORE wire in the air and thus MORE
wind loading and more motion due to a larger target.

This twist issue probably has its roots in the very early days of
telephony when the open wire telephone lines were regularly transposed
to reduce/cancel noise. Whether this has any (practical) effect today on
ham transmission lines is open to debate, but it certainly has nothing
to do with decreasing wind loading.


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