80m Dipole - Homebrew

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My Carolina Windom snapped yesterday as the wind came in and the wire took a hit from a branch close by to a insulated support. This will have rubbed over time and inevitably ended up weakening and shearing the wire flex.


My Windom antenna has been in use since 2004 and has served me well, I will repair it sometime. Today I fancied a change so I gathered some wire, insulators, a ferrite ring and a dipole centre which I used to construct a single band 80m dipole.
I started with two equal lengths of wire about 66 foot long which I soldered a couple of lugs to each end. I then found a short length of 50 ohm lightweight coax cable and wrapped it around the ferrite ring with 4 turns, following with a coaxial wound in a choke just below the ferrite.



Once complete I placed one leg of the dipole approximately 25 feet up and hooked it to the top of my F23 H antenna mast. I attached one insulated end to a telegraph pole and the other insulated end attached to a lower pole at the bottom of our garden. This install was easy enough with the help of my poly-carb 30 foot flag pole with a hook installed in the end I could do everything stood on the ground. I ended up taking the dipole up and down 3 times this evening to adjust the length to obtain a usable SWR. At present the SWR is 1:1 at 3.6 MHz and a little high at 2:5 - 3:0 on 3.8 MHz which will mean another adjustment will be necessary to obtain my preferred SWR reading of 1:1 - 1:5 at the top of the band. I will look into this over the week one evening possibly after work, in the meantime I am happy with the new dipole as I am hearing little noise and big signals from into G and EU tonight. I will catch a picture of the dipole up in position next post for you to see the installation as it was dark by the time I finished the install. The dipole will be under scrutiny over the coming weeks, I am feeling confident that it will be good as my initial findings are looking positive. I will be getting back to you with my results in due course, for now have a good week and I shall catch up with you all again soon. 73!

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