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Active loop

Ian
 

Thinking of purchasing an active loop and the ccw loop looks favourite. Having built a design off the net from m0mlk website, the mechanical construction of the loop I built as an inverted pyramid like the ccw.
Problem is I'm struggling to get a decent null on local electrical qrm. Wonder if the ccw loop offers a decent null? My loop is only about 2m off the floor.

73 Ian

Chris Moulding
 

The null of the loop antenna in a local ground wave station is very sharp.

If the source of interference is a similar point source the null would be equally sharp.

Unfortunately you may have several noise sources and it may be radiating from long lengths of electrical wiring.

2m is low for any antenna. Try mounting the loop antenna at some height. We used to run a loop antenna with a multiband WebSDR set-up some years back. The loop antenna was mounted 9m above ground and it really performed well lifted up above all the local noise sources .

I recall the one time the WebSDR server fell over was due to the amount of listeners listening to the one radio amateur on HF from Nepal after the earthquake. From what I found out later my WebSDR server was the only one that could hear him and many listeners and organisations wanted to listen in!

The old maxim "Height is everything for antennas" applies to loop antennas too.

Regards,

Chris