[TowerTalk] Verticals above chain Link fence

[Mark - N5OT]

Hi Ed,

Do I understand correctly that you have two antennas and you are asking 
about making changes to one of them?  If the other antenna does not 
change, then you could compare the new unusual design to the other 
design that has not changed, and you would know the answer.  If it was 
me, I might be inclined to "put it up and see what happens" but be 
advised that this approach is slovenly and without merit to some, which 
could open you to disparaging public comment, regardless of how loud 
your signal becomes because of the new antenna.

For the humor impaired, that was a little bit of a joke really.

Actually if it was me, given that you only need two resonant radials to 
make a complete system when they are above ground, and from what I 
understand this works when the two radials are symmetric about the 
feedpoint, I would not be able to stop myself from digging out some 
ribbon cable and cutting it so that I had one wire in the ribbon cable 
per band per side that was the right length.  then I would have 
everything I need in a single assembly with a single attachment point at 
each end, per each side of the feedpoint.

Then, I would mount it so that the radials were also symmetric about the 
fence.

Some wax poetic about tuning the radials for resonance, but I, being 
confident the system was symmetric, would not look back at that, I would 
cut the radials to approximate a resonant dipole, feed the whole thing 
with a matching network located for my personal convenience, I would 
make the radio happy with a swell SWR, and get on the air and work other 
radio operators.  Comparing it to the other antenna could yield 
confidence or concern, a not-inappropriate currency in my way of looking 
at it.

Bear in mind, it's possible the exact ribbon cable one uses might turn 
out to be too small.  This is easily determined without math as 
follows:  Put it up.  Use it.  If the ribbon cable heats up, it is too 
small.  If the ribbon cable does not heat up, it is not too small.  
Flames could be an indication too.  Watch the SWR while doing the 
experiment.

You might be able to do it differently than I have described and achieve 
what some would call "better" results, which would be an arguable 
statement, and then the argument about the results and how to measure 
them (seasoned with comments about engineering practices), would occupy 
the posts of this email reflector in the grand style to which we have 
become accustomed.

Or, you could do what I have described and get on the air and enjoy 
radio contacts from your warm cozy shack during the cold winter that 
will soon be upon us.

And thanks for getting me thinking.  I might have to go outside and try 
that.

73 - Mark N5OT





On 10/1/2019 9:52 PM, ed_richardson at shaw.ca wrote:
> Getting ready for another contesting season from my Postage stamp size City Lot.  In previous years I have installed a winter antenna (Steppir Vertical) in the rear yard as a second antenna to the tower mounted beams. In the past I have had had so-so success laying out 50-60 radials around the base of the antenna.. The problem is there is a lot of ground clutter such as trees and wooden fence in close proximity to the antenna.
>
> I was considering mounting the antenna about 13-15 above the ground and above a 7 foot high chain link fence. I was then planning on using 2-3 resonant radials on each band (40/30/20/15 forget about 10m).
>
> Has anyone had any experience with a similar configuration? Obviously keeping the radials away from the fence would be important.
>
> Thanks for the bandwidth!
>
> Ed VE4VT
>
>
>
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