If you neglect the radiation losses of the wide spaced open wire lines
on the higher frequencies, there are no bends in the line, and there are
no intrusions into the space about the line, open wire lines do actually
have lower losses than coaxial lines. In the REAL world where lines have
to connect to antennas, wire spacings are an appreciable fraction of a
wavelength, pass by towers and through window sash, and if the impedance
range of the antenna isn't too far from that of the coaxial line (not
true for a full wave center fed dipole) good coax can often has
adequately small losses, under a quarter dB.
73, Jerry, K0CQ
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Entire content copyright Dr. Gerald N. Johnson, electrical engineer.
Reproduction by permission only.
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