Paul, twisting or transposing the line is done in an effort to minimize
unbalance introduced by nearby objects. It is common practice to twist
the plastic ladderline - about 1 or 2 twists per foot - when installing
it. In my case, I have never been able to put any up without it twisting
itself very conveniently.
Power lines are commonly transposed to control line inductance, although
balance control may play a role here as well.
72/73, George
Fairview, TX 30 mi NE Dallas in Collin county
Amateur Radio W5YR, in the 54th year and it just keeps getting better!
R/C since 1964 - AMA 98452 RVing since 1972 Kachina #91900556
Paul Christensen wrote:
>
> >the tuner to the window feedthru plug. Beyond the window feedthru is 14ga
> >ladderline with a slow twist.
>
> What benefit is derived from twisting the feedline? Is it physical or
> electrical? From the 1920s and '30s issues of QST, I often find
> descriptions for adding "transposition blocks" on the feedline every few
> feet. This, in effect, forms a twist on the line as well, except that the
> twist is the reverse from the prior twist or transposition. If
> transpositioning the feeder was so popular then, why don't we see the
> technique discussed and used today when using balanced line?
>
> -Paul, W9AC
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