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Folded Weirdly (part 2)

capture_002_19092013_195620

The mean lifetime of my simple wire antennas is relatively short, and my folded weirdly antenna for the 40m band was no exception.
http://spinorlab.wordpress.com/2013/09/19/folded-weirdly/

Last weekend I re-installed the element with supposedly almost the same configuration, but this time with each leg of the element to be 10m long.

7MHzDpAnt

With the usual measurement it is observed that at 7026kHz CH1=2.943V, CH2=2.638V, and CH2-delay=+12.60nS.

gnuplot> load "gnuplot.txt"
Freq [MHz]=7.026
V1=2.943
V2=2.638
Cursor 1=1.26e-08
Cursor 2=0.0

vratio=0.896364254162419
phase1 [deg]=31.869936
phase2 [deg]=0.0

abs(gamma)=0.530090794923996
swr=3.25614135325678
cz={20.4433917939881, 26.9131366419314}

7MHzDpAnt2a

With a Smith chart and a physical cable length of 20m (remember the velocity factor of 0.66), you start from a red point (Zdut=20.443+j26.913), rotate towards load (not towards generator!), and end with a green point (Zant=27.182-j40.050), which shows the radiation impedance of the antenna.

7MHzDpAnt3

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Good for both audio and ham radio lives?

capture_001_21032014_104059

While I was not engaged in ham radio for the last almost 30 years, I was being a kind of a audiophile for some time. The figure shows one of the devices I obtained during that period, the model NSIT-2000PLUS Mark II.
http://ns-t.com/en/products/trans/nsit2.html

It is an isolation transformer, mainly used for your audio power amplifiers, and coverts 200V AC input to 100/115V AC output, with optional separate smaller transformers for your less power consuming equipment, such as an A/D and/or D/A converters;
http://spinorlab.wordpress.com/2014/03/02/orpheus/

Do you think this device is also effective for your rigs which deal with RF signals?