Topband: Loop discussion

[W2pm at aol.com]

In a message dated 5/18/2006 3:22:33 PM Eastern Standard Time,  
rudys at 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.