No I wasn’t. I was shooting about 931 feet to the roof of an hotel about 10 storeys high. My radio was about 30 feet off the ground. Now it’s 75 feet up and no issues.
Probably a strong reflection causing multipath.
I’m with Jerry.
Multipathing in the RF environment can cause all kinds of strange effects.
This is why RF is somewhat of a dark science. You can crunch all the numbers you want but it comes down to what happens when it is in operation in the specific environment.