Electronic signal, energy buildup:
-
Morse code transmission
-
Morse code, SOS signal reception
-
SOS signal transmission, Morse code
-
Pink noise
-
Geiger counter
-
Low-frequency rumble, high-frequency squeak
-
Low frequency pulsing and humming signal
-
Welcome, Morse code
-
High frequency squeak
-
Energy buildup, Electronic signal
-
Brown noise
-
Electronic signal
★★★★★