As an example of 20 meter propagation, these are the ham stations I received yesterday between noon and 5:00PM using the "FT8" digital mode (see attached image). This is from my house near San Francisco
. FT8 is a very slow / sensitive digital mode, but many of these transmitters were running low power
-- under 25W.
Later on last night I was monitoring 40 meters for a while, and was decoding stations over a similar range, although mostly north of the equator.
So it's going to be a matter of frequency, time, location, and luck, and making sure that you don't have a local noise
problem. At my house there is a furnace that blanks out 20 meters with S-9 levels of noise
when it is running. When that's going on I can only hear the very strong signals.