[Antennas] coaxial balun

[George, W5YR]

Charles, you are exactly right and thanks for jogging my ancient memory.
While I never used one that way, I seem to recall now of reading about
using a 1/4-wave matching section of 75-ohm line for the transition between
50 ohm coax and a 100-ohm load, and coiling the 75 ohm coax to form a
balun.

Clever way to nail both those birds with one rock!

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

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Charles Greene wrote:
> 
> At 09:31 PM 1/2/2002 -0600, George, W5YR wrote:
> 
> Hi George and Paul,
> 
> George is correct generally speaking.  I once made a coax balun consisting
> of a 1/4 wave length of RG59 (still have it), 75 ohm coax to do a match to
> 50 ohms and also convert between balance and unbalanced for a 15 meter lazy
> H antenna which was on the order of 100 ohms.  It is of course a 1/4
> wavelength on just 15 meters, but the antenna was for just 15 meters
> too.  Unless you have a specialized situation, just feed your dipole with
> RG-8 or RG8X type coax, there's no need for the LMR-400 in the HF band, or
> use a 450 or 300 ohm ladder line and an antenna tuner and get all band
> coverage.  If the coax does not comes off the dipole at right angles or
> nearly so, you can use a 1:1 balun at the antenna to reduce unwanted feed
> line radiation.  The information for construction a coax balun is in the
> ARRL handbook.  They say don't use RG8X coax for a coax balun as the center
> wire creep toward the braid, but RG8 or RG58 do a reasonable job.