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Old November 18th 07, 06:14 PM posted to rec.radio.amateur.antenna
Richard Clark Richard Clark is offline
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First recorded activity by RadioBanter: Jul 2006
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Default Low Noise receiving Loop antenna

On Sat, 17 Nov 2007 23:14:01 -1000, Tony Giacometti
wrote:

No. The main loop will still be tuned to the same frequency, no
matter if direct fed, or with a coupling loop. Many people build BC
loops and use the ferrite bar antennas in the portable radios
themselves to couple to the loop.

how do I calculate the dimensions of the coupling loop?


Hi Tony,

It has 1/5 the diameter and is a single, shorted loop.

Please don't try to make it more elaborate than it should be. One
wire, in a loop, connected to the other side of the feed (i.e. the
wire runs from the center conductor, 'round the circumference, to the
outer conductor).

Of course, this demands that the bigger loop be equally, simply
described. It too is one piece of wire, turned in a circle, each end
connecting to the resonating capacitor. In this case, you want to
optimize for the lowest Ohmic connections and materials. This may
suggest hardline, but, please, don't think of using the inner
conductor for anything at all - that is a waste of time. You could as
easily use copper tubing.

You can put more effort into it, but it will reward you only in the
sense of being the owner of a fine piece of furniture.

73's
Richard Clark, KB7QHC