In a message dated 5/18/2006 3:22:33 PM Eastern Standard Time,
rudys@ordata.com writes:
This current loop antenna discussion has been replayed continuously since
the 1920's in both professional and amateur circles, usually with more smoke
than light.
If you want to know how a loop works get a copy of:
R.E. Burgess, The Screen Loop Aerial, Wireless world, October 1939, Vol. 16,
page 492
There are also other discussions and references in Terman, Jasik, etc.
A small loop is just a Faraday's law device. If you understand Faraday (V=n
(dphi/dt)) and a dash of Ampere's law, the discussion converges quickly.
73, Rudy N6LF
But the whole thread (and the article!) misses the points that (1) the mag
loop is a poor antenna in the firstplace since it only has a positive effect on
the S/N ratio by nulling out a particular noise source (usually local) and
(2) it's has no elevational directivity - a donut on it's side essentially in
pattern - which actually exacerbates the S/N ratio. Its great for improving
the S/N on local Q's and will help with some single hop DX but my
observation is that you can still copy the DX better with the main TX antenna
even
through the huge noise level. A MFJ nuller is a better investment than a Mag
Loop.
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