[Lowfer] Active whip antennas

[riese-k3djc at juno.com]

Bill
did you measure or see any difference if the probe was in a tree
which would make the support ?
I understand that isnt a good idea but it would be one possibility for me

Bob K3DJC
 
On Sun, 19 Dec 2010 19:32:28 -0500 Bill Ashlock <ashlockw at hotmail.com>
writes:
> 
>  "I wonder if anyone has tried that experiment at a more open site, 
> perhaps hauling the antenna up a wooden mast that wasn't a tree."
> 
> John and all,
> 
> You may remember an experiment quite a few years back where I set up 
> my E-probe and potable SVM in an open field where trees were at 
> least 200 ft away. I raised the probe mounted on a insulated pole in 
> incremental distances and measured the signal output on the SVM from 
> a constant signal source many miles away. Turned out that the signal 
> strength was very close to being proportional to the height of the 
> probe. I was careful to have plenty of coax laying on the ground at 
> all probe heights so that the capacity of the shield to ground did 
> not vary in any significant degree and was considered very large in 
> comparison to the probe's input capacity to gnd.
> 
> Bill
> 
> 
> 
> > Date: Sun, 19 Dec 2010 18:43:45 -0500
> > From: w1tag at charter.net
> > To: lowfer at mailman.qth.net
> > Subject: Re: [Lowfer] Active whip antennas
> > 
> > > 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.
> > 
> > I wonder if anyone has tried that experiment at a more open site, 
> 
> > perhaps hauling the antenna up a wooden mast that wasn't a tree.
> > 
> > John A.
> > ______________________________________________________________
> > Lowfer mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/lowfer
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:Lowfer at mailman.qth.net
> > 
> > This list hosted by: http://www.qsl.net
> > Please help support this email list: 
> http://www.qsl.net/donate.html
>                                                
> ______________________________________________________________
> Lowfer mailing list
> Home: http://mailman.qth.net/mailman/listinfo/lowfer
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Lowfer at mailman.qth.net
> 
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> 
> 
 
____________________________________________________________
How to Fall Asleep?
Cambridge Researchers have developed an all natural sleep aid just for you.
http://thirdpartyoffers.juno.com/TGL3141/4d0ea5cd5b676df5a9m03vuc