Topband: Feedline Choke Placement in RX systems

[Adrian]

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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