[Elecraft] K3 Multi-Band antenna thoughts

[AE4CW]

Mike, I'm having very good results with a 136.5 foot OCF dipole (1/3-2/3) fed
with 120 feet of 300 ohm ladder line to an Elecraft BL-2 balun and one foot
of coax to the K3.  The SWR at the radio is less than 1.8 and as low as 1.2
across all of 80, 40, 20, 17, 12, 2/3 of 10 and even the first 1/4 of 6
meters.  I can send you the detail results measured with an Array Solutions
AIM 4170 if you like.  This approach keeps the SWR on the ladder line very
low (less than 3:1) on these bands and makes tuner loses very low as well. 
Total loss out to the antenna is less than 1 dB.  Plus it works on all the
other bands including 160 with SWR's within the range of the K3 tuner,
though with greater loss.

The length of the Ladder line is definitely a factor and I found that
modeling and theory don't always match reality.  In this case it turned out
that 120 feet was close to ideal; 100 feet was OK but not as good.  I also
found out that running the ladder line inside, though ceiling and walls,
made almost no measurable difference and you avoid the higher loss of coax.

BTW, I did the modeling work on EZNEC and then used TLW to figure out
transmission line and tuner losses.  And the good news is that the real
world results were even better than the model!

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Chuck, AE4CW
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