I've been having difficulty over the past few months trying to hit my favorite D-Star repeater from my QTH. It's weird, nothing in my "control" changed - but one day, out of the blue, I could no longer hit the repeater with 2-3 watts of power.
Anyway, over the past weekend, I just finally resolved to move "things" around and see how that might play out - and guess what! Yeah, it worked. I relocated my 2m/70cm vertical to another location in the back yard and I'm back to hitting the repeater with just a couple of watts of power.
Sometimes I wonder how any of this stuff works at all...
73 de KJ4WLH