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first time building a dipole from scratch, got some questions about the feed point

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so ive been licensed for about 8 months now and finally decided to stop borrowing my elmers old HF antenna and just build my own. decided to start with a simple 40m dipole, nothing fancy. cut the wire to roughly half wavelength using the 468/f formula, got some 14 gauge stranded copper wire from the hardware store, and threw together a center insulator from some thick PVC i had laying around.

my question is about the feedpoint connection. i soldered the coax braid and center conductor to the two wire halves but im getting kind of a weird SWR reading — like 1.8:1 at the calculated resonant frequency which i guess isnt awful but i expected to get closer to 1:1 without a tuner. the antenna is only about 25 feet up in kind of an inverted V configuration if that matters. wondering if the height is what's throwing things off or if my feedpoint connection is just bad. i did wrap the coax around a piece of pvc a few times as a kind of ugly balun thing but not sure if i did that right either

also the wire lengths ended up being like 33.1 and 33.2 feet because i ran out of wire on one side and had to splice a little bit, could that asymmetry cause problems?

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1.8:1 is honestly fine for a first dipole, most rigs will tune to that no problem and if you have an internal tuner itll barely blink at it. but yeah the inverted V configuration changes things — when you droop the ends down like that the feedpoint impedance drops from the typical 73 ohms you'd expect from a flat dipole, so you end up matching closer to 50 ohms actually which should help, but the height definitely matters too. 25 feet on 40m is pretty low, youre going to have a lot of ground interaction messing with the resonant point.

the splice on one side shouldnt matter much electrically as long as you made a solid mechanical and electrical connection. id be more suspicious of your ugly balun — wrapping coax around pvc works but you need enough turns and the diameter matters. common mode current on the outside of the coax shield can really skew your SWR readings and make the antenna look worse than it is. try adding more turns or use a proper 1:1 choke balun with a mix 31 toroid if you can get one, makes a noticeable difference.

dont stress too much about 1.8, i ran my first 40m dipole for two years at that SWR and worked plenty of stations. though i will say once i got it a little higher up — i was around 30 feet — it dropped down noticeably closer to resonance without changing anything else. height really does matter more than people think when youre that close to ground. also did you account for velocity factor when you cut the wire? not as much of a factor as with coax obviously but still worth checking your math

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