hi, everybody;

i am interested in constructing a choke balun for balancing a doublet
75 metres long, centre-fed with 30 metres of ladder line, an l-match
between the rig and the feeder;

i have read around a bit, including roy lewallen's splendid article
below; it seems that a balun maintains balance best when its inductive
reactance outweighs the line impedance by a factor of at least 4;

at about 2 mhz, the impedance at the bottom of my feeder will be high,
resulting in considerable imbalance on the line (more so that the
frequency is low, where the balun's inductive reactance is lower); i
have two questions;

1) would a balun at the antenna end of the line (where the impedance
is much lower) maintain balance in both antenna and line?
2) and then how about another balun at the l-match end of the line,
for frequencies where the antenna-end impedance is high?

your assistance would be appreciated; best wishes

--
http://eznec.com/Amateur/Articles/Baluns.pdf