On 2008-06-23, VK3XL wrote:

with 50 ohm coax. Due to the layout of my yard it would be preferable
that I feed the antenna at the mid point of one side of the antenna
with 450 ohm open wire line to a tuner (4:1 balun included in the line
and coax to the tuner). Is there any disadvantage in feeding the loop
mid way along one leg rather than at a corner?

Your radiation pattern will probably change somewhat, perhaps to the better
for what directions you desire. If you can model the antenna with software,
this will give you somewhat of an indication.

Just for information, I have a horizontal 80m delta loop fed with 450 ohm
ladder line which goes to a ferrite bead balun (W2DU style, built from a kit
from Wireman) to go from balanced to unbalanced and a short (less than 6'
coax) into the house to the tuner, an MFJ 941E. It tunes all bands 80m up
through 10m very well and performs excellently. Not the greatest DX antenna,
of course, but serves me well. Notice, this is a delta (three cornered) loop
and not four sides, due to yard size and tree locations. I feed my loop
about mid-side for convenience of feedline house entry.

73 ...Edwin, KD5ZLB
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