Anyone have problems running a KLM antenna with the 4:! balun and elements
insulated from the boom (stock KLM config) on a shunt fed tower for 160? I
ask because I have a 6 element 10 on the top of my shunt fed tower and
now, after running a kw on 160, the antenna's swr has gone over 2:1 where
before it was pretty flat at about 1.2:1 or so. Any ideas?
You probably ruined the balun from 160 current. The best cure would be
installation of RF chokes from elements to boom on all of the elements.
Anything over a few dozen ohms on 10 meters works for the parasitic
elements. They are not critical.
For 10 meters, I would use a good 4:1 voltage balun with the coax grounded
to the boom, or you can use a 4:1 current balun if you use a center tapped
choke of at least 1000 ohms and less than 2000 ohms on ten meters with tight
mutual coupling across the winding.
It would not be difficult to build some.
Remember the half-wave of coax makes a voltage balun, so you might as well
just save space and get more bandwidth by using a standard compact 4:1
voltage balun.
73 Tom
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Stew Perry Topband Distance Challenge coming on December 29th.
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