Tuesday, April 15, 2014

Many thanks

to those of you who posted comments, or sent me private e-mails concerning the 9:11 UNUN, and particularly to "Anonymous" who provided the link to: http://www.balundesigns.com/servlet/the-102/QRP-9-cln-1-Unun-1.5/Detail

That was an eye-opener.  If the weather isn't too chilly or damp this weekend, I think I am going to see what happens when I use the 24.5' and 36' wires as the radiator.  As my friend Bob W3BBO says, this is the fun of playing around with homebrew antennas - playing around until you discover something that works for you.  It will help if propagation is decent - it's never a great day to evaluate an antenna when just about no one is around!

The 24.5' wire would allow decent SWRs on 40 through 6 Meters (according to the chart, the highest SWR would be on 17 Meters at 2.1:1), while the 36' wire would allow decent SWRs on 80 through 6 Meters (according to the chart, the highest SWR would be on 20 Meters at 2:1).  In either event, this should work better than what I had previously tried, where I was getting a 3:1 SWR or higher on some bands.

I know there's no "one size fits all' kind of solution here. If there was, someone would be either very rich, or very famous.  My concern is to be able to go to the park, toss one manageable wire into a tree and get as much operating time in as possible.  Multi-band doublets might yield better results, but at a cost of increased setup time as well as the need for two supports. Another simultaneous goal is to be able to switch bands as much as possible, without messing around with wires too much after the initial set up.

I know - about as easy as trying to change lead into gold.

I'll keep you who are like minded posted as to what I discover.

72 de Larry W2LJ
QRP - When you care to send the very least!




2 comments:

Edward Haddock said...

Larry,
I am looking forward to what you come up with. I have an FT-817ND on the way and the smae EARCHI 9:1 BALUN. I took the wire off of it to use on another antenna a while back and now need to put a new wire on it. I enjoy your blog a lot.
Edward,
WH7TT

Steve Roberts said...

Hi Larry,

I've been using (and selling) a slightly different version of the EARCHI antenna and have had great luck with it. I use 31' and it works great. I'll be doing some more testing when the wx gets better using various lengths. It would also be interesting to see just how much the length of the coax effects the efficiency of this design.

Steve, W1SFR
KX3Helper.com