Morse code, SOS signal transmission:
-
Low frequency electronic signal
-
Low frequency pulsing and humming signal
-
Radio Setup
-
Pink noise
-
High frequency pulsating electronic signal
-
Morse code, SOS signal reception
-
Radio noise
-
Electronic signal, energy buildup
-
Morse code, reception, transfer
-
High frequency signal
-
Brown noise
-
Welcome, Morse code
★★★★★