[Amps] MOSFET amp filtering - was: auto-tune

Jim Brown jim at audiosystemsgroup.com
Mon Dec 12 22:34:41 EST 2016


Tom,

"Take-off angle" is a highly flawed concept for trying to understand how 
antennas work. Take a look at the links I posted. You won't see the 
words "take off angle" anywhere in the discussion. Rather, I've modeled 
the vertical and horizontal field strength performance as these soil and 
height parameters are changed and plotted the results on the same axes. 
When you do that, you learn what really happens.

73, Jim K9YC

On Mon,12/12/2016 7:03 PM, Tom Thompson wrote:
>
> Jim,
>
> /Lousy soil does NOT vary the vertical angle, it simply attenuates the 
> signal.  In the near field, it burns transmitter power by warming the 
> worms. In the far field, it degrades ground wave and weakens the first 
> reflection that creates the vertical pattern./
>
> Lousy ground does raise the take off angle of the maximum point on the 
> lobe of a vertical.  EZNEC shows the maximum point on the take off 
> lobe going from 18 degrees with very good ground to 26 degrees for 
> rocky mountain ground.
>



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