so ive been going back and forth on this for a while now and figured id just ask. i do a fair bit of hilltopping on 2m and 70cm, mostly just activating summits for SOTA and occasionally trying to work some weak signal stuff if conditions are decent. right now im running a Diamond X50 on a push-up mast which honestly does pretty well for FM simplex and hitting the local repeaters but i keep wondering if a small yagi would open things up more for SSB contacts and just general reach.

the thing is i dont really have a beam heading preference when im on a summit, i kind of want to work in multiple directions depending on whos calling back. so i was thinking maybe a 5 or 6 element dual band yagi that i can rotate manually but then again if im rotating manually whats the point over just using the collinear and having 360 coverage. maybe a small 3el on 2m is enough for a noticeable gain difference without sacrificing too much. anyone done both and have a feel for the real-world difference in practice not just on paper

yeah i went through exactly this a couple years back. ended up building a 5el 2m yagi from a design i found on the DK7ZB site and it made a genuinely noticeable difference for SSB, like contacts id never have made with the vertical just happened. but you're right that the rotation thing gets old fast especially on a windy summit where you're trying to hold the mast and spin it and log at the same time. what i do now is bring both - the collinear goes up first for the FM/repeater stuff and if i want to chase weak signal i swap it out and just accept i'll miss calls from directions im not pointing. realistically on a summit youre usually working toward population centers anyway so i just point toward the city clusters and call it good. a 3el is probably fine honestly, the jump from 3 to 5 elements isnt huge and the 3el packs down so much smaller.

whats your feedline situation on the summit? because if youre running any length of coax up to the antenna the loss on 70cm especially will eat into whatever gain advantage a yagi gives you anyway. i found that out the hard way with a longer run of RG8X, thought the yagi would be a big improvement and it was fine but not as dramatic as i expected. switched to a shorter run of LMR-400 and that actually helped more than going from 3el to 5el did. just something to think about before spending money on a new antenna