The feedline (if coax) outer braid responsible for imbalance RF
radiation, is fed from the antenna end.
Choking it there eliminates a RF active length.
vk4tux
On 1/12/21 03:48, Dennis W0JX via Topband wrote:
K9YC made an interesting comment in his post, saying that the feedline chokes
would be most effective if placed at the antenna end of the feedline.
W1FV's 9 circle YCCC array has them right at the controller.
The older K7TJR combiner utilized no feedline chokes. However, I believe that
Lee's new design has built in common mode protection on the combiner circuit
board.
So what is the best way? Is placement dependent upon the combiner design?
BTW, K3LR is using 2.4 in #31 toroids with at least 24 turns of RG-179 as
feedline chokes in his 8 circle HiZ array and I believe that there are chokes
on both ends of the antenna feedlines. Of course, K3LR operates in a high
intensity, multi-transmitter environment and may need all that choking.
73 Dennis W0JX
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