Mike K9MI wrote:
> One of the new Generals in town has purchased a 30ft pushup mast, the 4 band
> Hustler trap vertical (around 21.5 ft) and wants someone to install this for
> him with the mast bolted to a side of his house. Hustler shows elevating the
> antenna similar to what he wants to do (actually he wants someone else to do
> the work), with 2 radials for each of the 4 bands.
>
> I've tried to get him to ground mount the vertical close to the center of
> the backyard and put his radial system in the ground a few inches. He
> doesn't think that is a very good idea. Where he wants to place the vertical
> on the mast and, he will only have 180 degrees to work with in separating
> the radials. I don't see that he has 8 places to tie them off to.
>
> I've never used an elevated trap vertical. I don't know how critical the
> length and tuning of the radials would be and how important it is that you
> have 180 degree separation between radials of the same band. And is the
> difference worth the hassle over ground mounting with a decent radial
> system? Ground mounting is what I used as a novice with a 14 Avq (around 28
> years ago) , and that seemed sufficient to me at the time.
>
> I'd appreciate other opinions, and replying direct is fine.
>
>
Your friend is much better off getting the hustler off the ground.
Ground mounting is the latest fad but in reality ground mounting a
trapped vertical is considered a LAST RESORT!
They really perform much better as roof mounted antennas and only need
about 2 to 4 tuned radials per band.. In fact this is the preferred
installation as ground mounting a trapped vertical is considered an
absolute last resort.
Consider this, if you ground mount the Hustler you will need to bury a
minimum of 2000 feet of wire and even that won't compare to the
performance he will see at 30 feet with just 2 radials per band. Trust
me I know this from experience.
In my experience if your elevated radials are only 4 to 10 feet off the
ground then their not really elevated radials. Why bother elevating them
you might as well bury them and get them out of the way.
When I had my 6BTV roof mounted at 30 feet I started with about 4 tuned
radials per band. I eventually increased that to about 120 radials. My
poor roof looked like a spiderweb. Anyhow it made almost no difference
whatsoever, and it was a heck of a of work for nothing.
Now when we sold the house and moved, I could not roof mount the antenna
so I ground mounted it. I once again started with about 4 radials per
band but this time performance was dismal. I ended up burying close to
3000 feet of wire in about 120+ radials I lost track of how many are
down there. But the difference in increasing the number of radials with
ground mounted verticals is dramatic, But even with over 3000 feet of
buried radials the performance is still way below what is was when it
was roof mounted with only 4 radials per band.
Ground mounting has become popular not because it works better but
because DX engineering sells all sorts of neat accessory's to assist in
ground mounting.
73
KF6PYF
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