Parallel balun problem with wire loop
Where do I begin?
Let me say that I need help analyzing a dual-balun problem with my short
loop. I have a configuration that is working great, but other than that
it shows that I know next-to-nothing about why it is working ...
I have a short wavelength (about 0.10 wavelength long) wire loop
attached to the balanced port eyelets of a 1:1 voltage balun from W2AU.
I am using twin-lead feedline but get this: the feedline is ALSO
attached to the the balanced port eyelets of the voltage balun. The
unbalanced port with the SO-239 jack is unused and unterminated. THIS
is driving me crazy since it seems to work.
At the end of my feedline I am connected to my tuner's 4:1 internal
voltage balun. (An old Swan/Cubic Tee-type tuner).
I definitely need the loop balun, otherwise my loop becomes a noisy
omnidirectional random wire. This wacky configuration seems to be the
only thing that keeps the whole system balanced, and I don't know why.
(I have also tried using a current balun (W2DU), but it also turns my
short directional loop into a random wire.)
It just plain looks wrong even though it works great. I'd appreciate
some feedback on my funky configuration. Since the antenna covers many
bands with the tuner, I make no attempt at matching the feedline
impedance to the loop, and use a tuner to resonate the whole system.
I've made a web-page about my projects in case you want to look at it
and laugh. My project site has info about my experiences with
coax-loops, but I have since moved on to plain wire loops since they
seem to perform as well or better than the coax-made ones.
htt://www.greertech.com/gpmag/gpmagloop.html
You can find the remote configuration at the bottom of the page.
I just can't explain what's going on here and could use your help. Many
thanks in advance!
73 de LoopFan
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