[TenTec] Re: Ten Tec antenna tuners

George T. Baker w5yr@att.net
Fri, 31 Mar 2000 18:22:53 -0600

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

FAQ on WWW:               http://www.contesting.com/tentecfaq.htm
Submissions:              tentec@contesting.com
Administrative requests:  tentec-REQUEST@contesting.com
Problems:                 owner-tentec@contesting.com
Search:                   http://www.contesting.com/km9p/search.htm