The proportion of current that flows back down the shield compared to
that which flows into the attached dipole leg will depend on the
relative impedances of those two paths. In the case of a half-wave fed
one third from one end, the two leg impedances are almost identical:
319Ω/-87.7 degrees for the short leg and 334Ω/+72 degrees for the long
leg in a 132ft dipole I modelled. That suggests there'd be little
difference whichever side you connected the braid.
But of course, if you put a 4:1 voltage balun at the feedpoint the braid
isn't connected directly to either leg :)
Steve G3TXQ
On 25/01/2015 19:20, Stan Labinsky Jr. wrote:
OK, it just crossed my mind... happens once in a while.
If you're feeding the Windom with co-ax and you expect the shield to
radiate, which of the legs is the shield tied to? The long one or the
short one?
I would expect that it would make a difference.
Stan
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