Based on the idea of SWL amateur PA11019 (John) I made a J-Pole from with a matching section made out of coax (RG-58U). John has a nice webpage where he presents his experiences with some interesting antenna designs. http://pa-11019./ It is a 1/2 wave radiating section with a 1/4 wave matching section. Its length is shorter because of the velocity factor of coax. The feedpoint is made out of 2x PL259 and a Tee of 2x SO-239 1x PL-259. This opens up the possibility to use the radiating section and the first part of the matching section also for other antenna constructions hi. The antenna I build and get very good reports from. The feedpoint tap in the matching section. The matching section is shortened at the end and sealed with tape. Note: Fixing the antenna wire to a GFK mast is easy. The top of the mast is hollow and ends with a small hole. I used a big paperclip that I cut in two and soldered to the wire. Works quite well. Note that the clip adds up to the overall length. Hook the clip into the mast and twist the wire arround the mast (otherwise the whole weight is hanging on one paperclip in a small hole :-) web traffic analysis |
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