so ive been running a center-fed dipole for 40m for about two years now, got it up about 30 feet in an inverted-V config and its been decent enough but ive always wondered if a vertical would do better for DX. the dipole obviously has some nice gain broadside but the low angle radiation on a vertical theoretically should beat it for skip distances right?

anyway my buddy lent me his old trap vertical, one of those MFJ jobs, and i put it up in the backyard on a 4 foot ground rod and ran maybe 8 radials out at various lengths because thats all the wire i had. did some comparisons on 40 at night and honestly the vertical sounds noisier, like noticeably more noise floor, but the DX signals on it seem maybe a hair stronger? hard to tell because band conditions were jumping around all evening and i wasnt being scientific about it at all.

curious if anyone has actually done a real A/B comparison on 40m between a decent dipole up at like 0.3 wavelengths versus a vertical with a proper radial field. i know the radials are key and 8 is not enough but even with that caveat wondering what your experience has been

yeah the noise thing is real and its probably the biggest practical difference nobody talks about. verticals pick up a ton of local QRN because theyre omnidirectional and close to the ground, your dipole in inverted-V is actually rejecting some of that noise off the sides and ends. so even if the vertical is technically hearing a slightly stronger signal from a DX station the SNR might be worse and thats what actually matters for copying.

that said 8 radials on an MFJ trap vertical is leaving a lot on the table. ive read the ARRL studies and basically you get most of the benefit from going to like 16-32 radials and then it starts to taper off. with 8 youre probably losing a dB or two in efficiency versus a well-built radial field. and trap verticals have their own losses baked in from the traps themselves so its already starting behind a resonant wire antenna.

for pure casual DX on 40m late at night i actually think a fan dipole up at decent height beats a mediocre vertical more often than people expect. now if you could put up a full quarter wave vertical on 40 with 60+ radials on the ground thats a different conversation

I did basically this exact comparison a few years back, had a 40m dipole in inverted-V and tried a vertical I homebrewed from some aluminum tubing. ran about 20 radials which still isnt great. the vertical was definitely louder in every sense — more noise, more signal, just more everything. whether that translated to better contacts was kinda situational honestly. for Japan and Pacific stuff on 40 at sunset the vertical seemed to have an edge but for EU from the east coast the dipole broadside held its own pretty well.

one thing i'll say is if your inverted-V apex is only at 30 feet youre not getting great low angle radiation out of it either so both antennas are kinda compromised in their own ways. if you can get the dipole up higher thats probably the easiest win before messing around with a vertical and all the radial work that comes with it