On Mon, 7 Nov 2005 12:07:30 -0600, "RB"
wrote:

Got a Radio Works choke balun I'd like to use for feeding ladderline out of
an unbalanced tuner.

The balun has coax fittings on each end.

I think from the sound of your description you have one of their
"isolaters" that has a coax socket on both ends.

These things are very neat when used to "choke" currents on the outer
of coax.


Ladderline doesn't adapt well to coax interfaces.

What's the best way to put ladderline to my balun coax fitting?

I can kluge a PL-259 plug onto the ladderline.

I guess I could also stick one side of the ladderline in the center hole of
the chassis coac fitting, and clamp the other side to the threaded part of
the chassis fitting.


That doesn't sound reliable, the "stick one side of the ladderline in
the center hole" bit, that is. How would you maintain reliable centre
contact. (BTW, you probably already know that 4mm banana plugs fit
into SO-239 neatly.)

What is your problem, is it the "inelegance" of soldering the openwire
ends to the coax plug, or are you concerned about impedance
discontinuity at presumably HF / 6m?

I am sure that you could look around and find adapters, I can think of
a few ways myself, but...

If it is not in the weather, I would just solder the ends of the open
wire to a PL-257 and screw in on. You could sleeve the end going to
the centre conductor to improve its flashover voltage if that is
likely to be an issue. (BTW, taking the earth side wire down inside
the PL259 and bringing it out the braid hole will give you quite a
neat finish.)

Owen
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