so i finally stopped putting it off and just built a 40m dipole from scratch. used some 14 gauge stranded wire i had lying around from an old extension cord project, center insulator was a piece of PVC i drilled out and ran the coax through. honestly it came together pretty fast once i stopped overthinking it.

my question is about the feedpoint impedance situation. im running it as an inverted V with the apex at maybe 28 feet, legs going down at roughly 45 degrees. i know the impedance drops when you do the inverted V thing versus a flat top, closer to 50 ohms which is actually kind of convenient. but when i did a sweep with my nanoVNA the SWR at resonance is sitting around 1.4:1 which i thought was fine but then i started reading about it and now im second guessing myself. is that normal for this kind of config or did i mess something up at the feedpoint. the solder joints look ok to me but i didnt do anything fancy with the coax shield braid, just soldered it straight to one leg.

also the resonant frequency came out a little high, around 7.15 instead of where i cut it for which was more like 7.1. does wire stretch or settle over time or do i just need to add a few inches to each leg.

1.4:1 is totally fine, dont even worry about it. most rigs these days will happily load into that without the tuner even kicking in. people get way too hung up on chasing 1.0 and honestly unless youre running a linear or something the difference is pretty negligible in terms of power getting to the antenna.

the frequency thing is real though. stranded wire has a slightly different velocity factor than solid and the height and angle of the legs affects the electrical length too. if you cut it in free space at the standard formula it usually comes out a bit short of where you want it. just add a couple inches to each leg and resweep, do it gradually. easier to cut off than to add back on. also the wire will sag a tiny bit over time if theres any tension and that can shift things a few khz but probably not enough to matter much.

yeah i had basically the same thing happen with my first homebrew wire antenna, the resonance came out higher than expected. someone on here told me the 468/f formula already has some fudge factor built in but it still varies depending on wire gauge and how close to ground your ends are and all that. i ended up cutting mine long to start and trimming down which worked better than trying to add wire later.

one thing i will say -- did you use any kind of choke or 1:1 balun at the feedpoint? running coax straight to a dipole without any kind of choke can let rf come back down the outside of the coax and that can do weird things to your swr readings and also just generally cause rfi problems in the shack. i made a simple air core choke just by coiling like 8 or 10 turns of the coax at the feedpoint and it made a noticeable difference on my setup. not saying its your problem but worth trying if you havent.