KC5CQA wrote:
"In the past, the minor tests that I have conducted did not really prove
that much."

That might imply that there isn`t much to prove. You might infer that
VHF and UHF transmission ranges are similar.

One fact is that communication is a case of signal versus noise. Path
attenuation acts on both signal and noise. At UHF, signals may be
weaker, but noise is weaker too.

Harmonics of strong signals some times compete with the signal you
would like to receive. The 5th harmonic production is usually
inherently weaker than the 3rd, etc. This can make UHF signals usable in
some cases when VHF signals are not.

UHF may be reflected or blocked by smaller obstacles then VHF, but UHF
also penetrates and propagates through smaller spaces.

Antenna gain is more feasible at UHF.

Consider TV coverage, UHF channels versus VHF channels. The difference
in coverage is small..

In the good old days, increasing the frequency often meant decreasing
equipment performance. Solutions have now been found to many UHF
equipment problems.

Best regards, Richard Harrison, KB5WZI