so ive been running a 40m half wave vertical for about two years now and its been decent but i keep hearing guys on the local net talk about how much better their dipoles are especially for domestic stuff. my yard situation isnt ideal, i can get maybe 35 feet of horizontal space on one side of the house before i hit the fence so a full half wave dipole at 40m is pretty much out unless i do an inverted V and hang the apex off the chimney or something.

the vertical is ground mounted with about 16 radials, not buried super deep just laying on the grass, and it works but i feel like im always fighting noise on receive. someone mentioned the dipole has better noise rejection because its more directional and lower to the ground pickup or something like that, i dont fully understand the physics there. has anyone actually A/B tested these two configurations on 40m and noticed a meaningful difference in practice, not just on paper

yeah the noise thing is real, at least in my experience. i had a vertical with a decent radial field and switched to an inverted V at about 45 feet apex and the difference on receive was pretty noticeable, especially for picking out weak stations under QRM. the inverted V is going to have a bit higher angle of radiation than a flat dipole at the same height but on 40m for regional stuff thats actually fine, you dont always want the low angle for anything under like 1000 miles anyway.

your 35 foot constraint is workable. if you can get the apex up around 40 feet and let the legs droop at maybe 120 degrees or so youre looking at something that will outperform most verticals with modest radial systems on receive. the vertical will still beat it for DX at low angles if your radials are really good but for everyday operating the inverted V is just more pleasant to use. less noise, a bit more gain broadside, and you dont have to worry about RF in the shack from ground currents.

16 radials is on the low side tbh, most of the modeling work suggests you want at least 32 to start getting close to the theoretical ground plane efficiency. i went from 16 to 60 radials on my 40m vertical and heard a real difference, maybe a couple S units on some paths. that said if your yard situation is limiting you anyway the inverted V is probably the easier win. less fussing around on the ground and you can tune it with a simple feedpoint choke balun and forget about it.