TxantxibiriRE: https://universeodon.com/@g7izu/116295755700399433
"Sporadic-E, or simply “Es”, is mostly a summertime phenomenon, peaking between May and September in the northern hemisphere, and October and March in the southern.
High levels of ionisation in the E-layer (80-120km altitude) cause radio waves to refract over long distances. A single hop can be somewhere between 400 and 2400km. Multiple hops are possible and in combination with F2 propagation, global communication on the 50 MHz band is know to occur." https://www.tvcomm.co.uk/g7izu/ #irratia