Re: Balun question

ve2pid wrote:
Hi to all,

Until now, I used a 4:1 Van Gorden Balun with an OCF dipole and of
course a coax line to the tuner. I am now trying a 450 Window ladder
line. For now, the antenna is still connected to the balun, but I
removed the coax from it, and I use the balanced line connector of my
MFJ-949E antenna tuner (a 4:1 balun is in that tuner).

My question: Should I remove the old balun or may I keep it, i.e. does
it has any influence even if the coax is removed?

I find it convenient since the balun is a good holder for the
antenna's two branches.
============================
Although this tread is ongoing for some time I respond to the original posting.

If an Off Centre Fed Dipole is directly connected to a twin wire feeder ,be it ladder line or 300 or 450 Ohms twin feeder ( please note I do not use the wording : balanced feeder) the current /voltage in the 2 wires at any point on the feeder will not be the same in magnitude and differ 180 degrees in phase ,hence IMHO the feeder will radiate, which should be avoided

If a symmetrical dipole is used there is a reasonable chance that the feeder will NOT radiate and if that indeed is the case you can call the feeder balanced. This can be checked for example by placing a (split) toroid type of RF current sensor around the twin feeder (differential current measurement).

So it makes no sense to connect an OCF Dipole directly to a twin feeder .

Frank GM0CSZ / KN6WH
.

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