so ive been running a diamond x50a on my roof for about two years now and honestly its been fine for hitting the local 2m and 70cm repeaters, no complaints really. but theres a repeater about 55 miles out that i can kinda hit but its marginal, sometimes it opens up and sometimes i get into the machine with a lot of noise and the other ops can barely copy me.

started wondering if a yagi would help but then i got to thinking — if i put up a yagi pointed at that one repeater im basically giving up the omnidirectional coverage i have now and id have to rotate it or just accept that im only pointing one direction. the x50a is up about 30 feet on a pushup mast and the feedline is about 40 feet of LMR-400 so i dont think the feedline is really killing me.

is there a middle ground here or am i just stuck picking between omni coverage and the gain i need for that distant machine. somebody mentioned a collinear with more elements but i thought the x50a was already pretty good, whats the actual real world difference going to be from like a 5/8 collinear versus something with more dBd on 2m

the x50a is a solid antenna, no issues there. the thing is you're probably only getting around 3 dBd on 2m with that antenna so a longer collinear isnt going to get you dramatically more — maybe another 2-3 dB if youre lucky and the pattern stays clean. for a 55 mile path to a repeater input thats probably not gonna make the difference you need.

honestly a yagi pointed at that repeater is the right answer if that link matters to you. doesnt have to be huge, even a 5 element yagi on 2m is going to give you 7-8 dBd and a tighter pattern which is exactly what you want for a specific path. you could just mount it fixed in that direction and keep the x50a for everything local. two antennas, a duplexer or a switch, done. i ran something similar for years before i put up a rotator — the fixed yagi actually worked better for that one path because i wasnt constantly fiddling with anything

yeah what he said about a second antenna is probably the way to go. i tried to chase more gain with a longer collinear once and was kind of disappointed honestly. went from a x50 type antenna to a taller 6dB collinear and on a marginal path it didnt transform things the way i hoped. the yagi for a specific direction is just a fundamentally different tool

also worth checking — is the 55 mile repeater on a good site? sometimes the issue is the repeater input antenna or the path itself and no amount of gain on your end is gonna fully solve it