so ive been wanting to build my own 40m dipole for a while now and finally got around to it last weekend. used some 14 gauge stranded wire i had sitting around and cut each leg to roughly 33.5 feet, threw a SO-239 chassis connector on a chunk of PVC for the center insulator and called it a day. got it up in an inverted-V config with the apex at about 28 feet using my pushup mast.

heres the thing though — SWR is sitting around 2.3:1 at 7.150 which isnt terrible but not where i want it. i was expecting closer to 1.5 or so. the ends are maybe 6 feet off the ground which i know isnt ideal. wondering if the high SWR is just the end height situation or if my soldering at the feedpoint is suspect. i did have some trouble getting the solder to flow right on that SO-239, the center pin specifically, it kind of looked dull when it cooled.

also not sure if stranded vs solid makes a meaningful difference at HF. figured i'd ask before i start trimming.

dull solder joint is almost certainly a cold joint — that'll mess with things for sure but probably isnt the whole story at 2.3:1. reheat it and get it to flow properly before you do anything else, its an easy fix and worth ruling out first.

that said, 2.3:1 on a first inverted-V build at 28 feet apex isnt actually bad at all, the ground proximity at the ends is loading the antenna and pulling the feedpoint impedance around. 40m dipoles in inverted-V are notoriously fussy about height, you really want the apex as high as you can get it and ends at least 10 feet up. 6 feet is basically on the ground electrically speaking.

stranded vs solid doesnt matter at 7mhz, honestly dont even worry about that part.

i had almost the exact same situation with my first 40m wire, except i had mine going from the house to a tree in kind of a slopewire setup and SWR was all over the place. turned out one of my connections at the feedpoint had a strand or two not making contact. anyway what helped me was just rebuilding the center insulator with a proper SO-239 and some ring terminals so i could actually torque the connections down instead of relying on solder alone.

also if you havent tried it yet, run the numbers through an antenna modeling program — even the free ones like MMANA or 4nec2 will show you how much the end height is affecting impedance. kind of eye opening honestly, i spent a whole evening messing with that instead of actually operating but it was worth it.