[Lowfer] Medfer Loop Antennas

[Bill Ashlock]

Les, did you read this posting of mine from last week?

>This tweeks my interest in Medfer sending from a TX loop standpoint. A few 
>areas I just looked at (assuming a 3 meter square loop):

>1. Still a "small loop"; IE: current distribution is equal throughout
>2. Radiation resistance up considerably from 185k
>3. 2" copper pipe can be used without a trip to the bank, thus reducing Rac 
>losses considerably from 185k values. This would easily make up for the 
>reduced input power. This pipe diam. can be used without special support 
>members.
>4. Loop doesn't have to be mounted much higher than ground level and can be 
>turned with a small low-cost rotator.

In plain English, a 3 meter per side loop constructed from 2" copper pipe 
should easily beat any other antenna out there for radiated power on the 
Medfer band! It would be really interesting, from my standpoint, to measure 
the effect of loop height above ground vs signal strength at various 
distances (skip and surface wave). Equally interesting would be the effect 
of a ground screen, at least twice the loop width, as described by Ted Hart 
(the founder of amateur TX loop activity since the early 80s.) in the older 
ARRL Antenna Books.

Bill A

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