Strength of Es signals

One thing that surprises many is just how strong some Es signals can be. For example, my 500mW 10m WSPR beacon was being spotted at +2dB S/N implying that even at microwatt level I could have been spotted. Also, my 10m antenna is a compromise and could be far better.

This is not always the case. Sometimes Es signals can be marginal. With WSPR everyone has a chance. It also works with much weaker signals than SSB or CW.