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Four-wire Unbalanced Feeder

Author: Edmund A. Laport

The applications for this design (Fig. 4.11) are similar to those for type IV, and the same type of construction can be used except for the duplication for two inner wires at high potential. The use of two wires provides means for obtaining lower characteristic impedances than normally available with the type IV design, when small conductors are used

Fig. 4.11:
Fig. 4.12:

. When h >> 3a,


When ρ1 = ρ2 in inches,


A sample set of values for a useful low-power configuration is:
p (inches) h (inches) a (inches) k Z0 (ohms)
0.064 120 10 -0.55 248

Last Update: 2011-03-19