> From your description of your LW, you must have about 160 feet of
>antenna horizontal and about 100 feet vertical. That's a total of about
>a half wave on 160, a very bad length to try and match.
>
>Jerry, K4SAV
What is so difficult about trying to match a half wave antenna, fed at one end?
I have done this many times without difficulty, by using a parallel tuned
circuit, with one end connected to the ground system and the other end
connected to the antenna. It can be fed by tapping the transmission line a few
turns from the bottom end of the coil, or by winding a coupling link at the
bottom end of the coil. With proper placement of the tap or by carefully
adjusting the number of turns on the link, a perfect 1:1 match to the
transmission line can be achieved.
An alternative is to wire the transmission line in series with the bottom end
of the coil, with the shield of the coax connected to the ground system and the
centre conductor connected to the bottom end of the coil. This forms a simple
L-network. A perfect match can be had by adjusting the number of turns on the
coil along with the setting of the variable resonating capacitor.
Don, k4kyv
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