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Single-wire Unbalanced Feeder

Author: Edmund A. Laport

This design features the utmost structural simplicity, but its use is severely restricted to short runs at low or medium frequencies or to temporary installations. When the line runs over a buried-wire ground system, its attenuation may not be objectionable and when not too high above ground, its radiation is often tolerable. The characteristic impedance, being rather high, does not lend itself well to matching into low-resistance antennas. Unmatched, it can be used as a direct link between antenna and transmitter, with the tuning elements near the latter. For this type of line


Typical characteristics are:

p (inches) h (inches) Z0 (ohms)
0.50 120 509
0.100 120 466

Last Update: 2011-03-19