[450] Problem solved! Balun issue!

[George Andrews]

Bob,

 

The portable end fed will stay the same for size and weight
reasons. The balun that failed is that which came with the
Cobra Ultralight antenna. I could build my own, but am not
the best at putting things in nicely constructed packages.
As such, I am going with a commercial product. It is a Balun
Designs 4:1 voltage balun. It is rated at 3 kW, but is a
toroid design. I am told this design was tested at 2kW
without problems. It was the balun John Bee sells and was an
alternative from the Cobra Ultralight manufacturer. This is
it:
http://www.balundesigns.com/servlet/the-56/current-balun-4-c
ln-1-designs/Detail. May add a current balun as well, but
one thing at a time. 

 

I also plan to do the permanent end fed again. But instead
of the Unadilla I will use this:
http://www.balundesigns.com/servlet/the-106/9-cln-1-9-dsh-1-
unun/Detail

 

I expect the balun to come in as early as today possibly
tomorrow. As soon as I get it, I will be OTA with the amp.

 

Once we have thaw, I plan to get the CobraUL up higher, at
least 50 feet. I suspect that will improve the SWR on 40/20
M. I have not measured the height of antenna friendly trees,
but would like to have it at 85 feet. 

 

I understand CT is going to get snowed on heavily. Stay warm
and safe!

 

George

 

From: 450-bounces at lists.vhfwiki.com
[mailto:450-bounces at lists.vhfwiki.com] On Behalf Of Bob
Sent: Tuesday, February 4, 2014 6:27 AM
To: 450 at lists.vhfwiki.com
Subject: Re: [450] Problem solved! Balun issue!

 

Is this a step up balun on an end fed?  That is a little
tougher to find a suitable non-balun replacement for, but
for most things there is always a way to eliminate that weak
link.  I'd put my efforts in that direction and go QRO as
soon as possible!  

On Mon, Feb 3, 2014 at 3:26 PM, George Andrews
<gandrews at ntplx.net <mailto:gandrews at ntplx.net> > wrote:

Group,

 

I found the reason for my antenna problem. A Unadilla balun
came with the antenna, probably typical for a number of
commercial dipoles and wire antenna. The Unadilla baluns are
rated at 2kW. One would think that should not be an issue
when using only 600W sideband. What I did not think 

 

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