[Antennas] Gain with wire ...

[George, W5YR]

Tim, use a 1:1 current (choke) balun and let a tuner worry about the
impedance transformation. All you want the balun to do is to minimize
common-mode current on the coax braid. The impedance seen at the input of
your feedline is going to vary all over the lot with different bands so
there is little to be gained by attempting to somehow "transform" 450-ohm
ladder line to 50 ohm coax with a 9:1 balun. It would work, but only on the
band and/or frequency where the input Z of the ladderline was (a) 450 ohms 
and (b) resistive. 
These conditions can almost be guaranteed to never be present
simultaneously and it takes both for the balun to "work" as designed. It is
a far better solution to separate the tasks of impedance transformation and
balanced load feed from unbalanced line. Do the first with a tuner and the
second with the most effective balun that is relatively insensitive to
impedance and SWR levels: the current or choke balun.

I use three such antenna configurations here, two 20-meter EDZs and one
40-meter horizontal loop,  and each ladderline goes through a W2DU bead
balun to coax then to the tuners in the shack. There will be high SWR on
the coax on some bands, but if the length is kept reasonably short, the
losses are negligible. I can tune my EDZs on 80-10 with the MFJ 989C tuner
with no problems, no critical line lengths, etc.

You can buy W2DU bead balun kits or finished units at The Wireman - see any
QST for their ad. If you intend to be running max power - whatever than
means these days - then you will want to use ferrite core baluns wound with
parallel line or coax. See the Handbooks for info.

No rhetoric - just advice based upon sound practice and application.

73/72/oo, George W5YR - the Yellow Rose of Texas         
Fairview, TX 30 mi NE of Dallas in Collin county EM13qe   
Amateur Radio W5YR, in the 56th year and it just keeps getting better!
QRP-L 1373 NETXQRP 6 SOC 262 COG 8 FPQRP 404 TEN-X 11771 I-LINK 11735
Icom IC-756PRO #02121  Kachina 505 DSP  #91900556  Icom IC-765 #02437

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Tim Billingsley wrote:
> 
> OK there are three recommendations for the 300+ doublet
> http://www.cebik.com/edu6-1.gif can anyone tell me how to wind, make,
> fabricate, produce, simulate, or otherwise come up with a 9:1 BalUn. I run a
> TS570S(G) and I don't believe it has any provision for a balanced
> feedline(of course I am not staring at the back at the moment). I would want
> to utilize a BalUn and come into my shack with coax since I have aluminum
> siding, but not being an antenna Guru I am open to suggestions and comments
> on other alternatives ... after all that is why we are here I think.
> 
> Thanks again for the information and I patiently await rhetoric