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Helical Antenna for the 20- meter Band

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ANTENTOP- 01- 2013 # 017

Helical Antenna for the 20- meter Band

 

 

 

Figure 1 Schematic (A) and Design (B) of the Helical Antenna for the 20- meter Band

 

The input impedance of the helical antenna is strongly depends on the quality of the antenna grounding. With good antenna grounding the antenna should have input impedance around 8- 12- Ohm. For example, when I disconnected the antenna grounding system (www.antentop.org/017wires_017.html) and the antenna ground was only metal base of the microphone stand connected with the earth the antenna had input impedance 70- Ohm.

The low input impedance of the helical antenna is matched with 50- Ohm- coaxial cable with help of a simple ATU. Figure 2 shows the schematic (A) and the design (B) of the ATU. Parameters of parts of the ATU are calculated by me with the help of the free antenna simulator MMANA.

 

 

 

 

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Last Updated:

May 1, 2016 23:09

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