If I understand you correctly, you propose to put coax between the end of
your wire and the project box containing the balun (autotransformer). I
would recommend moving the box to the end of the wire, and using the run
of coax going back to the receiver to "come down" from the box to the
ground. This would, I admit, give you a problem of how to make the ground
connection to the coax shield at the antenna end; you could use a
grounding block, which requires your coax run to have connectors at this
point, or you need to do some "surgery" to the coax to take off the outer
covering without cutting the shield (for this, go to a sewing shop and
look at the tool called a "seam ripper", and you may see how to use it to
"uncover" coax shield).

This is a slightly funny antenna, the wire together with the exterior of
the coax shield, creates a grounded Inverted-L that has its feedpoint not
at the ground stake, but at the balun.

I've been playing with the idea of winding a coil with the coax at the
ground stake (back-of-envelope calculations say 200 uH) which makes this
antenna self-decoupling: at high frequencies, the high reactance
disconnects the "bottom" of the antenna from the ground, and it's a
bent dipole; at low frequencies, the low reactance makes it an Inverted-L.
One antenna for LW to 30MHz?

You asked for ideas...


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R F Wieland Newark, DE 19711-5323 USA 39.68N 75.74W
Icom R75 Heathkit GR-81 Inverted-L in the attic
Reply to wieland at me dot udel dot edu