Topband: QST Jun 06 RX Loop

Doug Waller NX4D at
Wed May 17 21:41:46 EDT 2006

>K3BU wrote:
>There`s a gap in the shield opposite the feedpoint. The gap prevents
>current circulation in the loop shield thereby making it permeable to
>magnetic coupling while shorting the electric field to ground.

Place ferrite beads over the ends of the shield adjacent to the shield gap.  
You will now find that the shielded loop no longer receives anything.
What happened to the shield's permeable magnetic coupling to the center 
wire?  Could it be that currents on the shield's surface were travelling 
around the end of the gap to enter the inside of the shield and then couple 
to the center wire?  Or mebbe the ferrite beads destroyed the shield's
ability to continue to be magnetically permeable?

If someone can explain this, I would like to hear it.

73, Doug / NX4D

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