A fellow ham has built a "Cebik" 44' doublet for his backpacking outings
but his tuner won't tune it on 40. Eznec says the feed point impedance
at 20' high is 20.7 - j629.6 ohms. He has tried inserting a balun.
Most
of the literature on baluns that I have seen never seem to describe
what goes on with the reactance part of the impedance.
Question 1
What would the feed point impedance be if a 2:1 balun is inserted in
an attempt to raise the impedance towards 50 ohms. What really
transformation of resistance and reactance occurs in baluns.
Question 2
According to my limited understanding of Baluns from Sevick's book
it is a bit of a misnomer to label baluns 2:1, 4:1 etc. as they are more
correctly 100:50 ohm, 200:50 ohm etc. as baluns have a characteristic
impedance? Furthermore is the 100:50 ohm (or 2:1?) only meaningful
when the connections to it are 100 and 50 ohms?
Question 3
Would a coil sized (+j629.6) to conjugate the -j629.6 help? How
should it be installed?
thanks & 73
k7puc
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