Date: Tue, 22 Jun 2010 12:54:46 -0700
From: "Dino Darling" <dino@kx6d.com>
Subject: Re: [TowerTalk] Have we been wasting our money?
Roger, stop stirring the pot! That CB antenna works perfect for what it
was designed for. The design was stolen from a guy named Kale who
builds the "Penetrator 10K" antenna. I know you are not so naive to
think that there isn't a huge outlaw CB market.
## anybody notice that the center loading coils in a cushcraft 402CD
[and probably the new version XM-240] have puny coils , wound with really small
ga magnet wire ?? Those coils have aprx 8.5 ohms RF resistance each !
The Un loaded Q of those coils is a joke.
## feed point Z = rad resistance + series losses. 32 + 8.5 + 8.5 = 49
ohms.
Sure, you end up with a low swr.. and that's about it. The ant is very
effective
however. They shoulda used way bigger coils.. and also big capacity hats
[f-12 calls em
T-bars] .. then you end up with a more eff ant. IMO, capacity hats are the
closest thing to
a free lunch you can get. F-12 opted for center loading on their sigma series
loaded yagi's
on 80 + 40m.... and used 3/8" OD AL tubing...[ and big T bars] Big diff
between puny small ga
magnet wire [close wound to make the UN loaded Q even worse].. and 3/8"
tubing coils.
## and folks are bashing 11m ops for using 3/4" wide bar stock for a coil..
and corrona balls ?
later... Jim VE7RF
Dino - KX6D
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