[Lowfer] Active whip antennas

[ToddRoberts2001 at aol.com]

In a message dated 12/19/2010 3:42:21 P.M. Eastern Standard Time,  
w1tag at charter.net writes:

So the 48 ft ground wire or coax shield will bring "ground" right up to  
the bottom of the preamp, and the output level from the preamp will be  
the same as if it and the 2 ft whip were on the ground? Don't think  so.

JA
 
 
No the output of the preamp will be higher due to the fact the antenna is 
higher up in the air and in the clear compared to being at ground  level
and surrounded by lossy obstructions like vegetation and trees, plus  being
further away from house wiring and AC noise. I have proved this myself by 
hoisting an active whip up into a high tree branch and observing the  change
in the signal to noise ratio.
 
And yes the coax shield will bring a ground reference right up to the  
active whip
preamp enclosure, if you use a good quality coax with a
good copper shielding braid like RG213. Cheap coax like RG58 with a lossy  
shield will not
bring a good ground reference up to an active antenna raised high in  the 
air.
 
73 - Todd WD4NGG