Hi all, quick question, as I cannot seem to find the answer for myself..
During flying school one was taught that VHF signals operate on a line of sight basis, and cannot travel through the earth or bounce on any ionosphere, and that that is what HF is for.
Only once in about 2 months or so, one can hear VHF transmissions at around 1000 ft, from aircraft broadcasting in their circuit, at an airport 480 nm south of my location, which is also at sea level.
The days are usually quite still and a little hazy, and I'm wondering what effect allows a VHF signal to travel much further that what it's conventional line of sight range would be, or if anyone has any idea as to whats going on
