so i've been putting off building my own dipole forever because i kept thinking i needed to buy something commercial, but last weekend i finally just did it with some #14 stranded wire i had sitting in the garage and a SO-239 chassis connector i pulled off an old project.

cut each leg to about 33.5 feet based on the 468/f formula for 7.150, got it up in an inverted V config with the apex at maybe 28 feet off a fiberglass push-up mast. center insulator i just made from a chunk of PVC pipe with some holes drilled through it, nothing fancy. ran 50 ohm coax straight down to the shack.

put the analyzer on it before connecting anything and it came back with an SWR of like 1.4:1 right at 7.150 which honestly surprised me, i was expecting to have to do a lot more trimming. bandwidth on 40 is usable basically across the whole band with the tuner helping at the edges. i did end up cutting about 4 inches off each leg to bring the resonant point up a tiny bit but thats it.

anyway the point is i wish i had just done this years ago instead of buying that multiband trapped vertical. the wire probably cost me less than 8 bucks total. if anyone's been on the fence about doing a homebrew dipole just do it, the math really does work out pretty close to right the first time most of the time.

yeah the 468 constant gets you close enough that you usually only need minor trimming, especially on the lower bands where a few inches doesnt matter as much. i built a 40m dipole a couple years ago the same way and i think i cut it maybe an inch and a half shorter total to hit where i wanted it. the inverted V does drop the feed impedance a bit compared to a flat top so sometimes people get a slightly better match at like 45 ohm-ish but honestly at 1.4:1 you're not losing sleep over that.

one thing i'd suggest is put a 1:1 choke balun at the feedpoint if you havent already, even just a few turns of coax through a mix 31 toroid or snap on. the coax shield can radiate and mess with your pattern plus it can bring rf back into the shack on 40 where common mode is a real thing. i skipped the balun on my first build and had all kinds of weird rf in the audio on certain freqs.

nice work. i built my first dipole about a month ago for 20m and it was kind of a revelation honestly. i way overthought it before i started. mine's just hung between two trees with some paracord and it works better than anything i was using before. the commercial HF antennas in my price range were all compromised in some way anyway so the homebrew route made sense.