James,
In your case, where you have the coax to the antenna buried underground, it
actually already has an effective choke on it. So you will probably find no
difference when adding another choke. However the choke will not hurt if it
is of proper design.
The problem when discussing the 43 ft. vertical is, it is an "all band
antenna" (they claim) but has totally difference impedance on the low bands
from what it has on the high bands. That's always a challenge. There isn't
going to be a single balun or unun that does both jobs best.
The 4:1 is OK for the high bands but a 1:1 would be better for the low
bands. Even better is Phil Salas' (AD5X) solution for loading coils at the
base, then switching them in and out.
Why am I saying the 4:1 is OK here, when I just said in another post it is
better to always use 1:1?
Simple, before we were talking about openwire feedline, now we are talking
about coax feedline.
I think the biggest problem most people have including me before I started
reading the right material on this subject, is we want to buy one device
called "balun" and have it do all jobs, no matter what. You can't drive
your 4 kids to the soccer match with a Corvette, but it's sure a nice
automobile!
73
Rick, DJ0IP
-----Original Message-----
From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Richards
Sent: Sunday, July 28, 2013 6:03 AM
To: Discussion of Ten-Tec Equipment
Subject: Re: [TenTec] which balun?
OK...
1) I use a 4:1 Balun Designs 4114ocf on my 40-10 meter OCF dipole.
2) I use a DX-Engineering 4:1 Un-Un on my 43 ft vertical, when it is set
for 43 feet, and no balun at all when I lower it to a 33 ft 40 m ground
plane antenna.
I considered a feed line choke... but DX-E was emphatic it would not be
necessary, and while I see no adverse result therefrom, I wonder whether a
feed line choke would still be a good idea, and I may try one anyway. In
contrast, I wonder why I should purchase a solution without first having a
problem...
3) I use a Cal-AV EB-2 Line Isolation Choke (purchased from Array
Solutions) on my rotatable dipoles made of aluminum tubing. (I see these no
longer appear on the Array Solutions web site...)
4) I have also used the Cal-AV EB-2 Line Isolation Choke on my
elevated vertical ground plane antennas, although I have been fortunate that
I cannot see any advantage with or without it, and a lack of problems is
always a welcome condition.
------------------- K8JHR --------------------
On 7/27/2013 10:59 AM, denton sprague wrote:
> Thought would start a little poll..
> Which balun are you using with your 238 series TT tuners and multi band
antenna?
> Currently, I use a balun designs 4214t 4:1 balun to feed my 80 meter
horizontal loop.with 450 ohm feeders.
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>
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