[Top] [All Lists]

[TowerTalk] Re: [DX] [Fwd: Low yagi question]

To: <>
Subject: [TowerTalk] Re: [DX] [Fwd: Low yagi question]
From: (lightfoots VE6PV)
Date: Sat, 5 Jul 1997 00:43:14 -0700
>GROUND   REFLECTION  coefficients depend SOLELY on HEIGHT
>above ground (in wavelengths).  A tribander's pattern will peak at
>different angles on the different bands because it's (fixed constant)
>height  is different for each band in terms of wavelengths.

>de  Tom  N4KG

NO. Wrong way around Tom. Ground reflection coefficients do not depend
solely on antenna height. In fact, the PERFORMANCE of an antenna at a
PARTICULAR height depends upon reflection coefficients. Remember that
mathematically, reflection coeffiecient is known as:

 Reflected Wave/Incident wave * /_(angle) in degrees.

This is a function of the ground characteristics, since it's the amount of
reflection will change with the incident angle. Since this is entirely a
GROUND characteristic, antenna height will only perform to the degree of
reflection coefficient for that particular ground.

So...the performance of the antenna at X wavelenths in height will DEPEND
solely on the characteristics on the ground (reflection coefficient). It
doesn't matter how high an antenna is, it does not alter the reflection
coefficient- it is always what it is,  since it is determined by the ground
conductivity and the physical shape of the ground itself.

I know, I know, I'm picking pepper again...... oh well IT'S BETTER THAN

73 de Shawn


Suggested Serving, Antennas not included.
|*                 *|
|*                 *|

FAQ on WWW:     
Administrative requests:

<Prev in Thread] Current Thread [Next in Thread>