Posted by
n6wg on
Apr 06, 2007; 5:00pm
URL: http://elecraft.85.s1.nabble.com/Buddistick-or-Buddipole-tp445377p445379.html
Hi Fred
Any antenna heavily loaded with coils will show a narrow bandwidth.
In effect, the coils and the capacitance of the antenna elements
across them form a tuned circuit. The higher the Q of the tuned
circuit (meaning the lower the coil losses) the narrower the
bandwidth, but the higher the efficiency. If you find a loaded
antenna with a large bandwidth, it is by definition much less
efficient due to the inherent losses.
There really is no free lunch.
Sometimes you can fudge a bit by tuning such an antenna to
the center of a band, and using an autotuner like the Elecraft
T1 at the feedpoint. Then, once you get away from the resonant
frequency of the antenna, it acts as if it were a simple nonresonant
centerfed piece of wire and the tuner will give you as good a
match as it can.
Good luck and 73
Bob N6WG
----- Original Message -----
From: "Fred (FL)" <
[hidden email]>
To: <
[hidden email]>
Sent: Friday, April 06, 2007 8:42 AM
Subject: [Elecraft] Buddistick or Buddipole?
> I've been considering the Buddi antenna, for a while
> now. It seems to be built well.
>
> One thing I've not been able to establish - is how
> much HF bandwidth does the antenna exhibit - once one
> sets the clips on those 2 coils, and gets resonance?
> I just wonder if a constant readjusting is necessary
> with this antenna, when we move up and down the
> HF bands? 20M CW then 20M SSB .......
>
> In other words - if antenna was all set up outside,
> would a HF user be required to continually adjust
> either the clips or the whips - when an operator
> goes from SSB to CW portions of the band, etc.?
>
> I tried some years back, to make a "dipole" out of
> Hustler mobile elements, with some adjustable whips
> - but never was able to get it to resonate very
> reliably. Those were in my no-tuner IC-730 days.
>
> Those are my questions regarding the Buddi line
> of dipoles and verticals, with coils and clips.
>
> Fred
> N3CSY, FL
>
> Very seriously considering one.
>
> Fred, N3CSY
> FL
>
>
>
>
>
____________________________________________________________________________
________
_______________________________________________
Elecraft mailing list
Post to:
[hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help:
http://mailman.qth.net/subscribers.htmElecraft web page:
http://www.elecraft.com