ANTENTOP- 01- 2012, # 016

Ground Plane Antenna for 40, 20, 15 and 10- meter Bands

Figure 1

"Active Antenna Input Resistance" Vs "Ratio Antenna Length/Working Wavelength"

Figure 2 "Reactance of Antenna Input Impedance"Vs "Ratio Antenna Length/Working Wavelength"

However, for to any antenna to radiate efficiently this one should be matched with the feeder. As usual it is not complicated to match an antenna in narrow frequency band. Antenna is matched with the feeder with help of a circuit that commonly consist of from capacitors and inductors.

The circuit that is called Antenna Tuning Unit does compensation of the antenna reactance and transforms antenna resistance to the feeder. However it is very hard to find such ATU that would be worked at several bands without changing parameters of its parts. But it was found off for the antenna! Figure 3 shows the ATU.

Figure 3 ATU of the Ground Plane Antenna for 40, 20, 15 and 10- meter Bands

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