Hello
Thanks everyone for helping this new guy out. As I said before,
this is my first hf vertical project and I have a big learning curve ahead.
The main things I've learned so far:
1) You can't have too many ground radials regardless of your type of soil.
You may have more than you need for best effeciency but all that is
wasted is some time and copper so go for it.
2) More & longer radials will lower impenence and increase swr UNTILL you match
the antenna
to feedline. The good swr reading with only a few radials masks the poor
effeciency (kind of
like a dummy load does).
3) More & longer radials will decrease the band coverage (tunung sharpens) so
you
really need some type of adjustable tuning system if you want all band
coverage..
4) Radial systems can and do affect the radiation pattern and angle but I
don't know
enough to go any further with that issue. Maby someday.
My idea of using a unun was an easy way out or so I thought. If I cut and tune
the antenna for 1/4 wavelength,
I could simply use the appropiate tap on the multimatch unun transformer and
I'm on the air but with out any bandwidth adjustments..
Probably the best idea is either cut it for 1/4 wl and add a homebrew LC
matcher at the antenna feedpoint OR
cut the antenna long (5/16 to 3/8 wl) and put a variable cap inline to tune out
the reactance.
Regardless of which option or even a future attempt to shunt feed the tower,
radials are going down as soon as
mother nature will cooperate. I've wasted time and money before on less worthy
projects so this has to work out.
Thanks all
JerryC
KC8TES
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