For a single band, stub matching is relatively an easy job. A short wire of length 30cm, described in my previous post (A little bit longer), is removed from each far end of the element, and Zant should be aound 14.025-49.337j [ohm]. (See Folded Weirdly for the detail.)
Now let’s try single stub matching using two 75 ohm coax cables, which I have in abundance. (Of course, you can use 50 ohm coax cables, if you prefer.)
gnuplot> load "gnuplot1.txt"
Freq [MHz]=7.026
V1=3.008
V2=3.731
Cursor 1=8.4e-009
Cursor 2=2.72e-008
vratio=1.24035904255319
phase1 [deg]=21.246624
phase2 [deg]=68.798592
abs(gamma)=0.47580332514932
swr=2.8153618593054
cz={42.3068002762323, 49.1623697140194}
The VSWR now becomes 2.81. Note that the length of 75 ohm coax cables is not adjusted yet, and is somewhat longer for both the cables than the values shown in the Smith chart.
