[TowerTalk] vertical antenna on tower from N0AH

[Dinsterdog@aol.com]

Jason,

When I lived in Denver, I  tried the R-7000 antenna a top a 40 foot tower 
then 8 feet off the ground.  And it seemed to hear a lot better closer to the 
ground.  The noise floor (where the average static level was on the meter) 
seemed slightly lower with the antenna on a 8 foot mast in the back yard 
garden vs 20 feet above my roof line.

 Of course, everyone's QTH can differ with what noises are in the air, but in 
my situation, which then was a back yard of a typical suburban 
neighborhood-it was a clear cut easy decision to leave the antenna near the 
ground.

 I may never have moved it if not for testing the R-7000 against my ground 
mounted Cushcraft AP8A multiband vertical.

Hands down, the AP8A heard a lot better .......and I really noticed the 
difference when working/hearing weak CW DX over the pole on 20 meters.  Many 
times, the ground mounted AP8A would have a clear copy on weak signal stuff 
that the R-7000 was not even registering up on the 40 foot tower.

I had them on a A/B switch for a few months so I could compare them side by 
side, -

On reports received, the AP8A would often get 1/2 to 1 S unit better reports 
vs the R-7000.  Not always, but often enough to make it the antenna of 
choice.  I would ask stations to listen to my dead key for a few seconds and 
compare the strengths of each antenna.

So I moved the R-7000 to a 8 foot mast off the ground in the back yard.  And 
guess what- it was tough to tell the difference between the two antennas on 
receive, while the AP8A still smoked the R-7000 by 1/2 to 1 s unit on reports 
received. Thus, moving it to the ground didn't seem to improve or worsen the 
transmit side- But at least the R-7000 noise floor was a little bit quieter 
enhancing it's reception--

Remember, I'm only talking about the weak signal stuff- Most of the DX 
sounded the same on either antenna-

But I say do everything you can to mount the vertical as close to the ground 
as the manufacturer's suggestions and safety factors will allow- - (I didn't 
have a lot of room in that back yard, and the antennas were wedge between a 
small space between a back yard deck and wood fence, so environmental 
influences aside......)- 

Also, I don't know if you are asking about an R-7000 or one of it's 
prototypes etc...but the reference to the "8 feet off the ground" question 
suggests it might be,  as this is a statement in the R7000 manual-  In case 
it is not,  I don't see trying to mount any type of vertical using a 
traditional ground radial system on top of a tower-  GL 73 

Paul  N0AH  from the NT7A Bridge Creek Radio Club Contest Headquarters 
located in wonderful Wyoming- 



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