[Antennas] Wire Antenna Questions/Opinions

[Dan Richardson]

At 12:55 PM 11/7/2002 -0600, George wrote:
>I use a parallel-coax balanced line made of two runs of RG-213. Shields are
>tied together at each end, floated at the ladderline end and connected to
>the tuner chassis at the input end. Zo is 100 ohms so SWR can be higher
>than ladderline SWR, of course.


Hi George,

I use exactly the same method as you. My parallel-coax run is only about 
three feet, however, this brings up a question in my mind I've had for some 
time. I've seem three recommendations on how the coax lines are to be 
terminated at the point where they are connected to the open line. One is 
the method you use. The second I found in the WireMan's Wire Book where it 
is stated that the shield portions are not bonded in any manner. If fact he 
goes on to say that care should be taken to assure they are not touching. 
And the third is a suggestion was by Lew McCoy (sk). He not only bonded the 
shields be he also made and earth ground connection at that point as well 
as grounding the shields at the tuner. The later method seemed to me to 
offer the possibility of having a ground loop problems - depending upon 
frequency and the length of the parallel-coax run.

I was wondering what your thinking on these other methods are and why you 
had chosen to use the method you are using.

73
Danny, K6MHE