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![]() hi there, i'm looking for some help with a j pole antenna, it's actually a vhf marine antenna so i hope it will be ok to ask here. my problem is that this antenna used be atop the mast of my yacht untill it blew off breaking the end fitting and pulling free of the coax, because these things are quite expensive and don't seem to last that long, I decided to try repair it as a spare. It fits inside a fibreglass tube, so I carefully cut through the tube and pulled out the antenna parts, which are all intact. my plan was to solder some coax to it and put it back in the tube, then glass the tube back together, but this is where i ran into trouble, i'm unsure where to afix the coax. the antenna i believe is a j antenna, with a 3/4 wave leg and a somewhat less than a 1/4 wave leg returning from the base, however there is no connections on this stub part where the coax has been connected, i had expected there would be. There is, however, 2 pins below the 2 upright legs, these are not electically connected to the upright stub elements, (the 2 upright elements are joined across the bottom). These 2 pins have a length of insulated wire attached to them which stretches over and parallel to the uprights of the stub. The 2 pins are staggered in height which means 1 side of this insulated wire run is approx 75 mm and the other side is approx 70 mm, it runs like an inverted v up the stub from these pins at the base. I'm assuming that the coax should also be soldered to these 2 pins and interacts with the antenna through induction or something. If this is correct does it matter which side of the coax goes to which pin, neither of them are conneced to anything other than each other through the insulated wire, which as i've said, runs above what i beleive to be the antenna stub section. or should the coax be connected at the top of the stub, ( a halfwave from the top), i can't see any sign that the coax was previously fixed there, but then there is no sign that it was previously connected anywhere for that matter hope this makes sense and someone is able advise, thanks for looking and if you can help thanks again. if this all sounds like nonesense, i may be able to put a picture as an attachment but i'm unsure whether it is acceptable in this group. kevin |
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