antenna coupler help for medium waves?

[tzitzikas]

i have a transmitter 50 ohm output at 1431khz medium wave band. my antenna is an inverted-L antenna with (5/16)*wavelenght total lenght (20 meters
vertical and 45 meters horizontal wire 2,5mm). i have 3 scematics for antenna coupler system. The first and the second
schematic send me 2 radioamateurs. I calculate the third coupler with 4nec2 software. Which coupler is the best
for my antenna??? do you have to propose another schematic?
i have a variable capacitor 500pf and a variable coil about 100uH. thanks

http://www.sv9cvk.gr/images/KWcoupler/COUPLER.jpg
http://www.tzitzikas.webs.com/match.JPG
http://www.tzitzikas.webs.com/4nec2.JPG

 

[W5LZ]

Having no direct experience with what you are attempting, I would have to say that I think the first example would be the most versatile, in general. One of the other two may be specifically 'better' for your application.
How would you compare the second example and your 4NEC2 results?
- 'Doc