Been monitoring 15m, and first heard FT8 signals were at 1745z - 21075 kHz Thus the F2 layer on 15m is active. Austin Ionogram (30.4 Lat) is predicting MUF(3000) = 18.1 MHz at 1750z. MUF(3000) is a ~ 2 degree elevation angle MUF for F2 prediction. Bill W7EXG