[TowerTalk] matching to screwdriver antennas

Dan Sawyer dansawyer at earthlink.net
Wed Jun 2 23:52:59 EDT 2004


All,

Screwdriver antennas present an interesting matching problem. When fully 
retracted, typically 10 meters, the antenna is close to a resonant 
vertical and has an impedance of about 35 Ohms. However when extended to 
80 meters it has an impedance of about 1 Ohm radiation and say 5 Ohms 
coil. That is close to a 6:1 difference in the radiating element. For 
this let's assume a constant ground from 80 to 10 meters.

Is there any way to design a reasonable matching network for a 
screwdriver antenna??

Thanks,
Dan





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