I was trying to ignore this subject and let the tuner on the 765 or the
tuner for the Titan do my dirty work, but curiosity is getting the best
of me. The question of the month is :
Anyone have a method of matching the KLM rotatable 40M dipole to 50
ohms? My R-X bridge measurements yield a load impedance of 20+j20. The
swr at resonance is 1.7 and is about 40 khz wide. If I drop the swr to
1:1, I theoretically could get a wider < 2:1 band.
I tried to use the series matching method with a combination of 50 to 75
and back to 50 ohm coax, but one iteration of this will not work.
Should I do this twice? Should I add -j10 of C in series with each side
of the dipole and then try to match from 20 + j0?
How about Dr. Seviks un-uns or baluns. How do I wind a 1:.75 or 1:.4
transformer?
Does the normal 1:1 balun (50 ohms to 50 ohms) exhibit 1:1
characteristics at an impedance of other than 50 ohms?
This junk was not covered in my E&M classes, but I could sure do some
mean Bessel functions.
Now once I get this straight, I have another KLM element in the pile in
the backyard and a 20' 3" boom section from my old full size Wilson 2 el
40 M monster. ( I really miss that antenna...It was a flamethrower)
I may want to build a 2 el job. I assume I will meet with a similar
mismatch situation. Anyone have any experience with a KLM 2 el ?
The things you have to do when 10 M is bye bye.
Eric, NV6O
edwoods@pacbell.com
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