Paul W1VLF wrote:
Every now and then it seems neccessary to find several references on
a topic and approach it from a number of "different angles"
I agree. When Nick and Mike recently asked about the
relationship of current and voltage through/across a loading
coil, we were treated to excellent contributions from Andy and
from Rik (I'm glad that you sent your contribution, Rik - even if
it was an 'oops'!!).
This is the case with all this talk about ground systems, losses
in earth, trees, building, etc.
Can someone point me to a sight where some of this is explained?
You could start be reading the article "Build Efficient, Short
Vertical Antennas" by Thomas Kuehl AC7A (QST, March 1998, p 39).
There you will find the antenna system 'equivalent circuit' which
you seek.
Do trees shunt current to earth? There seems to be a million
different values that need to be considered!!!
Yes, in a way. The shunt path from our LF antennas to lossy
objects such as trees and buildings has an equivalent series
resistance - which serves to increase the resistance at the
feedpoint, thereby increasing the losses. You can read all about
this, and many other LF antenna topics, at the web site of Rik
ON7YD. See:
http://www.qsl.net/on7yd/136ant.htm
Confused in Connecticut. Anyone else in the same boat?
Rather less so, since I joined this Reflector!
Regards to all,
Steve GW4ALG
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