A little web searching has revealed much about the theory
of how balanced, shielded cable would work to reduce
common mode noise pickup. I also understand that
a balun will be required at the shack end to match
the unbalanced connectors on my radios and/or
tuners.
What is not clear is how the cable would be connected
to my low noise EWE antenna? I assume that one
connector would go to the antenna, and another to
ground? What about the shield; is it left floating?
To combat my noise on topband, I've just finished
relocating both my EWE and remote tuned air core
loop to the back part of my yard, and digging trenches
that are 16 inches deep (ditch witch). I've got 75ohm
quad shielded burial cable installed, with isolation
transformers for both ends.
Also installed virgin ground rods 10 feet deep into
the ground by each antenna, and filled those
holes with benonite. All in an effort to reduce
local noise pickup.
The balanced, shielded lines appear the better
way to go. Fortunately, I haven't filled in the
trenches yet, so it's not too late. Can someone
help me out with the connections? Also
are any commercial baluns available to
convert the twinax to 50ohms?
Could the same type of cable also benefit
my loop?
73,
Les Rayburn, N1LF
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